Journal of the Myanmar Academy of Arts and Science Vol. XI, No. 6

Transcription

Journal of the Myanmar Academy of Arts and Science
Vol. XI, No. 6
Contents
Section (i) Geology
Sr. No.
Title
Page
1
Tun Naing Zaw, Ohnmar and Zin Mar Myint, Landslide
Hazard Potentials along the Railway Road between
Kywedatson and Pyinnyaung, Thazi Township, Mandalay
Region
1
2
Kyi Kyi Linn, Zaw Win Ko and Aung Kyaw Thin,
Mineral Chemistry and Assessment of P-T Evolution Based
on Thermodynamic Constraints of Metapelitic Rocks of
Thetkegyin Area, Mandalay Region
31
3
Me Me Aung, Than Than Nu, Min Aung, Petrogenesis of
Metacarbonate Rocks Exposed in the Nyaungwun-Malegyi
Area, SinguTownship
47
4
Hnin Min Soe, Volcanic rocks, Ultramafic rocks and its
related Serpentinization of Maingna-Naungnan-Alam Area,
Myitkyina District, Kachin State
61
5
Su Su Hlaing, Petrography of Igneous Rocks in Tawmore
Taung Area, Longlon Township
83
6
Than Than Oo, Geology and Mitigation of Landslide
Hazard along Sittway-Mrauk Oo Car Road, Rakhine State
99
7
Moe Min Soe, A Study on Mineralogy of Gold Ores from
Myanmar Deposits
119
8
Aye Aye Han, Microfacies Analysis of the Linwe Formation
in the area, northern part of Bawsaing Range, Shan State
(South)
129
9
Me Me Thein, Myitta, Zaw Win, Sedimentological Aspects
of the Turbiditic Division of the Loi-an Group, Thazi and
Kalaw Townships
141
10
Yin Min Htwe, Myitta, Zaw Win, Silurian Transgressive
Rocks in the Linwe-Pegin and Yegyanzin-Wabya Areas,
Shan State (south)
151
Section (ii) Geography
Sr. No.
Title
Page
11
Nay Win Oo, Crop-Land Suitability Analysis in Hinthada
District Using a Multicriteria Evaluation and GIS Approach
165
12
Aung Kyaw, Ye Ye Than, Moe Moe, Kay Thi Aung,
Geographical analysis on the variation in agricultural
technology diffusion among the farmers near Taungoo
University
177
13
Nyi Nyi Aung, Geographical Analysis on Crop Cultivation
of Kyaukme Township
195
14
Htun Ko, Landslide Susceptibility Assessment along
Oaktwin-Paukkhaung Road within Khaboung Reserved
Forest Area
215
15
May Thu Naing, Environmental Perception and
Environmental Awareness of Residents in Layshi Township
of Naga Land
229
16
Yee Yee Than, Cho Mar Oo, Ei Ei Khaing, Myo Ma Ma
Wai , Cultural Diversification and Integration in Taungoo
253
17
Min Min Aye Than and May Myat Phone, A Geographical
Analysis of Markets in Thingangyun Township
279
18
Kyaw Kyaw, Geographical Analysis on the Socio-economy
of Coastal Area: the case of Daminseik Village, Mon State
297
19
Saw Yu May, Hnin Khaing Aye, Migration Patterns of
Hpa-an Township
313
20
Nilar Aung and Associates, Sustainable Development of
Floating Garden Cultivation in Inlay (Inle)
333
21
Khin Khin Han, Khin Khin Htay, Kyaw Khing Win,
Geographical Assessment on Settlement Patterns in Maubin
District, Ayeyarwady Region
351
Jour. Myan. Acad. Arts & Sc. 2013 Vol. XI. No. 6
Landslide Hazard Potentials along the Railway Road between
Kywedatson and Pyinnyaung, Thazi Township, Mandalay
Region*
Tun Naing Zaw1, Ohnmar2 and Zin Mar Myint3
Abstract
The study area, Kywedatson and Pyinnyaung railway road, is the part of the
Thazi-Shwenyaung railway road. Transportation in Shan State (south) relies
on the Thazi-Shwenyaung railway road, which supplies all the basic needs
for people. During the raining season, transportation is usually halted by the
occurrence of landslide along the railway road. The study area structurally
lies between two major fault zones which are Sagaing Fault in the west and
Shan Scarp Fault in the east. The bed rocks along the railway road between
Kywedatson and Pyinnyaung, are mainly composed of slate, calc-phyllite,
phyllite, leucogranite, microgranite, and diorite. Along the TahziShwenyaung railway road, landslide may commonly occur as rock-falls
which is more likely to occur on steep slopes, underlain by water-saturated
unstable materials. In the study area, landslide is triggered more readily by
heavy rains, rather than earthquakes alone. The main factors that influence
slope stability of the study area are geological conditions, erosion, rainfall,
slope gradient, vegetation, local earthquake and vibration by train driving.
Most of the slope failure occurs in slate and phyllite rock units. Moderate
slope failure occurs in diorite, microgranite and calc-phyllite rock units.
Minor slope failure occurs in leucogranite unit. The rail road was
constructed across the foliation plane of the rock units. So, plane failure is
more common in metamorphic rocks. Wedge failure can occur in the highly
jointed slate unit. Landslide zone can be divided into four types which are
stable zone, fair zone, serious zone and danger zone. Prevention of natural
landslides is difficult, but common sense and good engineering geological
practice can do much to minimize the hazard. The methods for controlling
and mitigating the land side potentials depend on many factors such as the
nature of the potential slide, the nature of materials, the amount of materials
involved and the economic considerations. Landslide warning systems do
not prevent landslides, but can process and stop coming train. Along
transportation routes in mountainous terrains, slopes are often too extensive
to be fully stabilized and trouble free. So, slope stability maintenance
systems are required.
Keywords: Landslide, hazard, rock-fall, slope stability, slope failure,
landslide zone, slope stability maintenance systems.
1. Assistant Lecture, Dr. Department of Geology, Taungoo University
2. M.Sc student, Department of Geology, Yangon University.
3.M.Sc student, Department of Geology, Yangon University.
* Best Paper Award Winning Paper in Geology (2012)
2
Introduction
The study area, Kywedatson and Pyinnyaung railway road, is the part of the
Thazi-Shwenyaung railway road. The railway road section lies between
Kywedatson village to the west and Pyinnyaung village to the east. It is located
between Latitude N 20° 45′ 00″ to N 20° 46′ 30″ and Longitude E 96° 16′ 15″
E 96° 23′ 15″, (Fig-1). During the rainy season, transportation is usually halted
by the occurrence of landslide along the railway road. Although the landslide
is one type of natural hazards, many controlling factors and methods can
reduce the hazard of the landslide. Prevention of landslide in the study area
along the existing railway is also very important, therefore, landslide problems
and potentials should be studied scientifically. This research mainly focuses on
the geological data and geotechnical data that are investigated in order to
understand the causes of
landslide along the ThaziShwenyaung railway road.
Research Procedure
Before
the
field
investigations have been
carried out, previous works,
satellite images, aerial photos
and literatures were studied.
Satellite image interpretation
in mainly based on Thematic
Mapper image with band 2, 3
Fig (1) Location map of the study area. and 5. Major rock units,
structural units, and regional structural patterns are classified and lineament
map is prepared (Fig-2 and Fig-3). Aerial photo interpretation is studied on
the scale of 1:50,000. The main aim is to find the faulted stream or valley,
major rock units, structural trends and drainage system along the railway road
between Kywedatson and Pyinnyaung. Geological structures and lithologic
differences are interpreted on conventional black and white photographs.
3
Detailed morphological analysis of the area is drawing the simplified
topographic map of the study area. The following field investigations and
laboratory methods are carried out in this research (Fig-4).
Field investigations
(1)
(2)
(3)
(4)
(5)
(6)
(7)
Locating the landslide potential point by G.P.S (Global Positioning
System) reading.
Measuring and identification of joint spacing and joint density by using
three meters diameter circle and one meter square.
Measuring the nature of joint blocks
Identification the nature of jointing in different rock types.
Collecting the geological structures for finding stress field position.
Collecting the geotechnical data for studying the engineering properties
of rocks.
Estimating the strength of different rock types by testing the point load
(3 lb hammer)
Laboratory methods
(1)
Calculating the joint density
(2)
Calculating the slope stability by using trigonometry.
(3)
Drawing joint spacing and constructing. The joint spacing correlation
tables by using excel computer function.
(4)
Determining of possible slope failure by using stereographic analysis.
(5)
Calculating the stress field by using stereographic analysis.
4
Research Procedures
Topographic map, Aerial photos and TM
images interpretations
Literature Review
Basic Concepts of Theory
- Structural Geology
- Engineering Geology
- Landslide
- Slope Stability
- Landslide Preparedness
and mitigation
Geological Map of the Research Area
- Engineering Geological map
Reconnaissance Field
Detail Investigation
Field
Investigation
Laboratory Works
Geotechnical Data
Geodata
 Orientation of slope
 Major discontinuities
 Geological structures (i.e. foliations,
faults, joints etc.)
 Try to give RMR, GSI and joint
density

Engineering
properties of
rocks
 Calculation of joint density
 Calculation of slope stability
 joint spacing section line and
correlation table
 stress field analysis
Interpretation
Landslide Hazard Preparedness and Mitigation
Fig (4) Flow chart of research procedures
Rock units of the study Area
The study area is situated in the mountainous region of the western
edge of the Shan Plateau. The bed rocks of the study area consist of slate,
5
phyllite, calc-phyllite, microgranite, leucogranite, diorite and rocks of
Pyinnyaung Formation.
Structural Analysis
Structurally, the research area is very complex and complicated. The
strike of the rock units are generally NNW-SSE. The major distinctive
structure is found as fault which is parallel to the general strike of the rock
units. Minor faults are occurred in the railway road.
Rock units of the study area and surrounding region.
Rock Unit
Age
Alluvium
Quaternary
Unconformity
Sedimentary Rock
Kalaw Red Bed Formation
Late Cretaceous
Unconformity
Pyinnyaung Formation
Late Jurassic – Early Cretaceous
Unconformity
Loi-an Group
Late Middle Jurassic – Early Late Jurassic
Unconformity
Upper Plateau Limestone Group
Middle Permian – Early Triassic
Metasedimentary Rock
Lebyin Group
Early Carboniferous
6
Rock Unit
Age
Igneous Rock
Dykes and veins
Biotite microgranite
Foliated granite
Late Mesozoic – Early Tertiary
Diorite and related rocks
Non-porphyritic biotite granite
Porphylitic biotite granite
Metamorphic Rock
Yinmabin Metamorphic
Lower Paleozoic
The Yinmabin metamorphic are folded into a major south plunging
syncline, namely as Kywedatson syncline. Numerous folds of varying size and
shape are present, especially very common in the metamorphic rock units.
Kink fold, drag fold and intricate fold are found in the study area (Fig-5, Fig-6
and Fig-7).
The study area lies between two major fault zones that are the Sagaing
Fault in the west and Shan Scarp Fault in the east. The minor faults are
occurred and their trends are NNE-SSW and E-W direction (Fig-8).These
faults may be associated with Sagaing Fault and Shan Scarp Fault.
Extensional stress direction of the normal faults are NEE-SWW, ENE-WSW,
NE-SW and NNE-SSW (Fig-9). And also the extensional stress direction of
the thrust faults are nearly E-W, (Fig-10).
Most of the rocks exposure in the study area is moderately to highly
jointed and their dimension, spacing, opening and in filling of joints with
various materials may be vary from place to place.
7
Fig (5) Kink fold
occurred in the slate
rock unit of the
study area.
Fig (6) Drag fold
occurred in the
slate rock unit of
the study area.
Fig (7) Nature of
intricate fold in
the
study area.
(a)
(b)
(c)
(d)
Fig (9) (a) to (d) Extensional stress position in
normal
fault of the study area.
Fig (8) Nature of fault
in the study area.
Fig (10) Extensional stress
position in thrust fault of
the study area.
The possible force directions of rocks in research area (1), in diorite unit
(108.89 degree, NWW-SEE in direction), (2) in microgranite unit (167.5
degree, NNW-SSE in direction), (3) in Lecucogranite (245.5 degree, NEE-
8
SWW in direction), (4) in slate (217.02 degree, NNE-SSW in direction), (5) in
calc-phyllite (131.3 degree, NNE-SSW in direction) (6) in rocks of
Pyinnyaung Formation (66 degree, NE-SW in direction).
According to histogram of the dip amount of the study area, high angle
or vertical joints are prominent (Fig-11). Therefore, the study area is situated
in lateral displacement zone. The distribution pattern of the orientation of
principle stress axis for joints in the study area are calculated and drawn by
stereographic projection. Maximum principal stress axis (σ 1 ) is nearly N-S in
direction (Fig-12).
Diorite rock unit
Slate rock unit
Microgranite rock unit
Calc-phyllite rock unit
Leucogranite rock unit
Phyllite rock unit
Fig (11) Histograms of joints on the basis of dip amount of various rocks unit
in the study area.
9
Diorite
J 1 = 88°/50°
J 2 = 74°/320°
σ 1 = 14°/N 2° E
σ 2 = 74°/S 38° W
σ 3 = 10°/S 85° E
(a)
Microgranite
J 1 = 72°/218°
J 2 = 68°/26°
σ 1 = 67°/S 520° W
σ 2 = 22°/N 34° E
σ 3 = 6°/N 56° W
(b)
Slate
J 1 = 60°/330°
J 2 = 62°/140°
σ 1 = 82°/S 32° E
σ 2 = 8°/N 35° W
σ 3 = 0/N 54° E
Phyllite
J 1 = 30°/190°
J 2 = 48°/300°
σ 1 = 20°/S 10° E
σ 2 = 30°/ due W
σ 3 = 44°/N 53° E
(c)
(e)
(d)
Calc-phyllite
J 1 = 48°/340°
J 2 = 70°/130°
σ 1 = 64°/S 14° E
σ 2 = 23°/N 42° W
σ 3 = 11°/N 54° E
(f)
Leucogranite
J 1 = 48°/30°
J 2 = 68°/230°
σ 1 = 66°/S 18°W
σ 2 = 20°/N 44°E
σ 3 = 33°/N 51°W
Pyinnyaung Formation
J 1 = 70°/160°
J 2 = 20°/78°
σ 1 = 54°/N 88°W
σ 2 = 20°/S 28°E
σ 3 = 32°/N 48°E
(g)
Fig ( 12 ) (a-g) The orientation of principal stress axes for joints in the rock units of
the study area.
10
Rock mass characterization and slope statiblity
Orientation of discontinuities
Orientation of discontinuities relative to that of an engineering
structure has an extremely important effect on the stability of the structure
which could be a rock slope itself.
Spacing
Spacing of discontinuities is directly related to the rock mass quality.
The shear strength of the rock mass increase with the increase in spacing.
Opening width
The opening width is the distance between adjacent walls of
discontinuity large aperture could be traced on massive rock units in the study
area. Maximum joint aperture is < 3 cm and minimum Joint aperture is < 1 cm
(Fig-13 and Fig-14).
Filling materials
Filling materials may change the shear strength considerably. The
filling materials at the study area are variable. Fault gauge is observed in the
fault plane of the diorite rock unit and its thickness is about 0.33 m (Fig-15).
The fault gauge is about 0.083 m thick in calc-phyllite rock unit (Fig-16).
Quartz vein occurred in the diorite rock unit (Fig-17). When the filling
material is thick, the shear strength will be reduced to that of filling material.
Number of joint sets
In the study area, Joint sets could be observed three sets or more which
are related the deformation strength of mass, amount and direction of tectonic
force with respect to pre-existing planes of weakness. Most of the Joint sets
are conjugate joint set and the prominent joint sets are trending nearly NNWSSE, and nearly N-S direction.
Weathering and alteration
In the study area, weathering or alteration grade is moderately to
highly. Joint plane alteration occurred in the diorite rock unit which alteration
is epidotization.
Diorite joint surfaces occurred the weathering process that is
Kaolinization. Oxidation process occurred in metamorphic rock units (Fig-18
and Fig-19). Microgranite is particularly resistant rock.
12
tabular shape can be seen in phyllite (Fig-24). Rhomb shape of calc-phyllite
can be seen in (Fig-25).
Fig (20) Rhombic block
shape in phyllite rock
unit
Fig (21) Triangular
block shape in slate
rock unit.
Fig (22) Rhombic block
shape in diorite rock
unit.
Fig(23) Cubical joint
block shape of
leucogranite
Fig(24) Weathered
tabular shape of
phyllite
Fig(25) Rhomb shape
of calc-phyllite
RMR Classification of jointed rock mass
The RMR (Rock Mass Rating) is the commonly used systems for
classifying rock mass, proposed by Bieniawski of the South African Council
for Scientific and Industrial Research (CSIR). Six parameters, measurable in
the field are listed as
Strength of intact rock
- Uniaxial Compressive Strength (UCS), and Point
load index (Is)
RQD (%)
- used as a measure of drill core quality
Spacing of joints
- used to mean all discontinuities, i.e. joints, faults,
bedding planes and other surfaces of weakness
Condition of joint
- accounts for aperture of joints, their continuity,
the surface roughness, wall condition (hard or
soft) and filling materials
13
Groundwater condition - observed rate of water flow
Orientation of joints
- used as an adjustment to the sum of the rating for
other parameters
Geological Strength Index (GSI)
Hoek and Brown (1977) introduced the Geological Strength Index
(GSI), both for hard and weak rock masses. This classification is based on the
following correlations and measurement in GSI (Fig-26)
GSI = RMR – 5 for GSI ≥ 18 or RMR ≥ 23
Measuring joint density
The abundance of jointing at a given station is described through the
evaluation of joint density. Joint density can be measured and described in a
number of ways: average spacing of joints; number of joints in a given area;
total cumulative length of joints in a specified area; surface area of all joints
within a given volume of rock. The measure of joint density used in
conjunction with the circle - inventory method (Fig-27).Following equation is
used for joint density.
where,
P i = joint density
L = cumulative length of all joints, and
r = radius of inventory circle
Fig (26) Measurement of GSI
Fig (27) Measurement of joint
density
14
Types of Landslides of the Study Area
Plane failure, circular failure, wedge failure and rock fall are
commonly occurred in this area. Among them (i) and (ii) involve simple
gravitational sliding and factor of safety can be calculated by applying the
method of limiting equilibrium in analyzing the slope failure. The wedge
failure and plane failure are the most common type of failure along ThaziShwenyaung railway road. The rock fall and circular failure are minor events.
Plane failure
Plane failure occurs at geological discontinuities, such as bedding
plane,
foliation, cleavage and joint plane. And also plane failure occurs
strike parallel to the slope face and dip in to the exaction at an angle greater
than the angle of friction ( ) sliding. There are two types of plane failure: (1)
a slope having a tension crack in its upper surface and (2) slope with a tension
cracks in its face.
These are two influences in plane failure, (i) influence of water
pressure and (ii) influence of under cutting the toe of a slope. The influence of
water pressure is quite evident that landslide occurs commonly during the
rainy season, especially after heavy rain falls which probably create
abnormally high water pressure. The undercutting of the toe of slope usually
leads to failure of slope. It can be observed that slope of the road cutting is
parallel to the discontinuity plane (Fig-28).
(a)
(G.P.S location - N 20º 45.745', E
(b) (G.P.S location - N 20º 46.074', E
º
º
96 17.924', Facing- 330 )
96º 17.756', Facing - 40º)
Fig (28) (a-b) Nature of plane failure occurred in slate rock unit.
Circular failure
Most of the circular failure occurred along the Thazi-Shwenyaung
railway road (Fig-29). The occurrence of circular failure was also observed in
15
the stream section. Only the abnormal water pressure is presumably
responsible for this slope failure.
Along the Yinmabin-Pyinyaung railway were found circular
failure, especially around from Pyinnyaung station to Yinmabin
junction at 58 milepost. Residual soil development is relatively good
along this road section. In this area can be found that soil and rock
debris are involved in circular failure. The occurrence of circular failure
was also observed in the stream section.
Most major circular failure is occurred when the slope stability
slope high is equal to or greater than 10 feet. During the raining season
along a tension heavy rain falls, water pressure is presonably
responsible for this slope failure. Circular failure occurred in Loi-an group
in (Fig-29, Fig-30, Fig-31, Fig-32 and Fig-34).
Wedge failure
Wedge failure occurs where the hill side is made up of bands of
strong and
Fig (29) Nature of circular
failure occurredin diorite
rock unit.
Fig (30) Circular failure of
Fig (33) Circular failure
of Pyinnyaung
Formation.
Loi-an Group.
16
weak material. This failure type occurs along the railway road. Parallel joints
are causing the conjugate joint sets. In highly jointed rocks wedge failure is
the most. Major joint blocking system, rhombic and triangular joint blocks are
found in this area (Fig-35, Fig-36, Fig-37, and Fig-38).
Fig (35) Nature of wedge failure
occurred in calc-phyllite rock unit.
Fig (37) Wedge shape of leucogranite in
the study area.
Fig (36) Wedge failure of phyllite
in the study area.
Fig (38) Wedge shape of
leucogranite in the study area.
Rock fall
Rock falls are a major hazard in rock cuts for railway in
mountainous terrain. Rock falls are generally initiated by some climate or
biological event that causes a change in the forces acting on a rock. These
events may include pore pressure increases due to rainfall infiltration, erosion
of surrounding material during heavy rain, storms, chemical degradation or
weathering of the rock, root growth or leverage by root moving in high winds.
The study area is situated generally in hilly area. The slope angle is 30°
but in some places, slope inclination is 60° because of steep slope cutting. The
17
vegetation is moderately dense in this area. This area is complex structure and
lithology .Diorite rock falls are fall down near the railway road section (Fig39). Very small rock falls were covering the railway road (Fig-40, Fig-41 and
Fig-42).
Metamorphic rock units are more causing the joint block and rock falls
occurred in near the railway road (Fig-43, Fig-44 and Fig-45). In some places,
small leucogranite rock fragmens occurred 0.057m away from the railway
section line (Fig-46). Rock falls are occurred in the Pyinnyaung Formatio(
Fig-47, Fig:48, Fig-49 and Fig-50)
Fig (39) Diorite rocks
falls are fall down near
the railway section.
Fig (40) Small rock falls
of slate rock unit.
Fig (42) Very small rock Fig (43) Rock falls
occurred in calc-phyllite
fall of slate rock unit
was covering the railway rock unit.
section.
Fig (41) Diorite rock
fall was covering the
railway section.
Fig (44) Small rock fall
occurred in slate rock
unit near the railway
road.
18
Fig (45) Rock fall
occurred in slate rock
Fig (46) Rock fall of
leucogranite.
Causes of Landslides of the Study Area
The main factors that influence slope stability of the study area:
a. Geological conditions
b. Erosion processes
c. Rainfall effects
d. Gravity and slope gradient
e. Vegetation effects
f. Local earthquakes
g. External factors
Geological conditions
The attitude of rock and their lithologic characters, structural planes or
weak plane, as well as surface jointing and weathering are very important to
evaluate the stability of the natural slopes. Weathering of rock mass and
weathering processes creates the permeable materials and these permeable
19
materials can cause the increasing of water pressure. Huge blocks sitting on
the hill surface are likely to slide down.
Erosion processes
Erosion processes are used by the continuous run-off over a slope.
During the rainy season, high flow velocity of running water in slope move
rock falls and plants that will destroy the railway road. Uncontrolled flow of
rain water on slope surface washes out boulders which threaten along the
Kywedatson-Yinmabin railway road.
Rainfall effects
The main trigger of landslide is heavy or prolonged rainfall. Rain
come into or inflow into the joint plane in rainy season. For study area,
rainfall season is from June to October. The average yearly rainfall for 2006 is
96.7mm, 2007 is 100.3mm, 2008 is 82.7mm, 2009 is 75.3mm, and 2010 is
120.1mm. The average rainfall from 2006 to 2010 in May is 155.6mm, June is
59.8mm, July is 64.6mm, August is 103.8mm, September is 163.2mm and
October is 162.6mm. May to October is highest rainfall. So, these months are
more favorable for the landslide potential (Fig: 51).
Gravity and slope gradient
Shear stress may cause movement of the body parallel to the slope. As
a slope become steeper, the shear stress becomes larger. Shear strength is the
internal resistance of the body to remove.
Vegetation effects
Root of the many trees penetrated along the weak zone and joint plane
in diorite rock unit (Fig-52). Rock blocking and fragmentation will caused by
intruded roots (Fig-53). Many trees are rooted along the foliation plane of the
slate rock unit (Fig-54). Joint planes are destroyed by root.
Local earthquake
The region of the study area falls on the active earthquake zone. Some
of great earthquakes have take place along the Sagaing Fault, which is running
north and south 16km far in west from the study area. The Shan Scarp Fault is
running north and south is located 19.2km far is east from the study area. In
the study area, the seismic zone is strong zone. For this zone, a probable
maximum range of ground acceleration in ‘g’ values is 0.2-0.3g and equivalent
20
Modified Mercalli (MM) scale class is VIII. (Maung Thein and Tint Lwin Swe,
2006)
Fig (51) Rock falls and plants fall
down from the top of the slope due to
the rainfall effect.
Fig (5) Plant roots penetrated into the
joint block in diorite rock unit.
Fig (52) Large root penetrated the
joint plane in diorite rock unit.
Fig (54 ) Many trees are attached
along the foliation plane of the slate
rock unit.
External factors
External factors, such as storms the torrential rain, and impact
groundwater regimes. Storms also produce intense rainfall for periods as short
as several hours or have a more moderate intensity lasting several days and
have triggered abundant landslides. The study area is railway road which is
having the train vibration effect. Therefore, this vibration can be caused the
landslide.
21
Landslide and Their Relation to Rock Types
As proceeding described, the wedge failure is the highest frequency,
the plane failure is second, rock fall is third and the circular failure is fourth.
The most occurrences of landslides along the Thazi-Shwenyaung railway road
are shown in (Fig-55). Most of the slope failure occurs in slates and phyllite
rock units. Diorite, microgranite and calc-phyllite rock units found in the
moderate slope failure and leucogranite rock unit is minor slope failure.
Fig(55) Slope failures type of the study area
Fig (56) Landslide potential and problem
map along the railway section
between Kywedatson and
Yinmabin Area, Thazi
Township, Mandalay Region
Fig (57) Landslide potential and problem
map along the railway section
between Yinmabin and
Pyinnyaung Area, Thazi
22
Fig (59) Engineering geological landslide hazard
Fig (58) Engineering geological landslide
map along the railway section between Yinmabin
hazard map along the railway section between
and Pyinnyaung Area, Thazi Township,
Kywedatson and Yinmabin Area, Thazi
Mandalay Region
Fig (60) Landslide zoning map along the railway
section between Kywedatson and Yinmabin
Area, Thazi Township, Mandalay Region
Fig (61) Landslide zoning map along the
railway section between Yinmabin and
Pyinnyaung Area, Thazi Township, Mandalay
Region
Landslide and Their Relation to Structure
The railway road was constructed across the foliation of slide and
plane failure occurs closely. Slope failures are also common in slate, phyllite
and calc-phyllite rock units. A high density of occurrence of plane and wedge
failure was observed in these rock units. However, rock falls occurred. Slope
height also plays a role in the occurrence of slope failure. Most of the major
failure occurs when the slope height is greater than 15m. In the study area,
bedding plane (S 0 ) and foliation plane (S 1 ) are generally trending nearly N-S
direction. They are in most places dipping steeply. Therefore, plane failures
occur when the railway road section is nearly parallel to the strike of these
discontinuities. Wedge failure, however, can occur in the slate are highly
23
jointed. Any failure can occur because of slow flatting due to weathering in
the study area. Landslide potential maps and engineering geological hazard
maps shown in (Fig-56, Fig-57, Fig-58 and Fig-59).
Landslide Zone Interpretation
Landslide zoning map is shown in (Fig-60 and Fig-61). This map
prepared by integrating the effect of various influential factors. Landslide
zone can be divided into four types which are stable zone, fair zone, serious
zone and danger zone. The study area occupied igneous and metamorphic
rock units. Igneous rock is good strength but metamorphic rock is moderately
strength. Stable zone didn’t occur the landslide potential and problem because
it is alluvial plane and small rock exposure. Fair zone is mainly composed of
igneous and metamorphic rock units which occurred the potentially unstable
slope. In metamorphic rock units such as slate and phyllite, very small
fragments are covered on the railway road. Rock fragments, unstable slope, a
few major blocking and fractures are occurred in serious zone. Rock
fragments are related to the fracture zone. The retaining wall situated in the
left side of the study railway road. This wall is 4m in height and width which
notice the absences of weep holes (Fig-62). Near the retaining wall can occur
the landslide problem and drainage course (Fig-63). Rock fragment residues
were fall along the cutting slope and drainage course which may be joint
surface.
Leucogranite fragments fall down into the stream in right side of the
railway road section. Near the Kyauk Pan O bridge, leucogranite rocks are
occurred the major rock block and unstable slope (Fig-64). Small retaining
walls are occurred in the calc-phyllite rock unit. First retaining wall is 7 m in
length and 2.6m in height and another one is 6.5m in length and 2.6m in
height. These retaining walls are not occurred the drainage holes and over the
calc-phyllite load is very heavy (Fig-65).
Slate rock fragments fall down from the top of slope to toe of the
retaining wall. This retaining wall is 35m in length and 1.67m in height. In
slate rock fragment width 5m is covering the retaining wall (Fig-66).
Danger zone has complex structure such as fold and fracture. Type of
fold is intricate and fracture zone is 0.08m width. This zone is high
deformation intensity and brittle deformation. Joint density value is nearly
1m–1. Retaining wall (5m long and 1.3m high) was
24
Fig (62)
The instability
of the wall and the lack of
weep holes.
Fig (63) Rock
fragmentation occurred in
microgranite rock unit.
Fig (64) Rock block
occurred in leucogranite
rock unit near the railway
road.
Fig (65) The lack of drainage
hole occurred
in the
instability of retaining wall.
Fig (66) Slate rock
fragments fall down on the
retaining wall.
Fig (67) The rocks fall
down over the retaining
wall near the railway road.
constructed on the unstable slope. This slope was occurred the slate rock
fragment which falls down over the retaining wall near the railway road
section (Fig-67). Tunnel occur the drainage holes and two ditches in left and
right side (Fig-68). In rainy season, rock mass block fall down on this tunnel.
So, this zone can be caused the landslide more and more. In the Pyinnyaung
Formation, rock fall of fragments are due to landslide of danger zone (Fig-69).
Fig (68) Two ditches and drainage
holes occurred in tunnel
25
Fig (69) Rock fall of Pyinnyaung
Formation
Recommendations and Discussions
The study area is situated in the railway road between Yinmabin and
Pyinnyaung, Thazi Township, Mandalay Region. Study area can be divided
into four major landslide zones which are danger zone, serious zone, fair zone
and stable zone. So we must do prevention methods where on the landslide
area. Mostly, common useful methods are rock bolting, anchor bar, benches,
retaining wall, rock crib wall and cutting slope, etc. Serious zone and potential
zone should be emphasized to prevent of landslide and the two other aren't
need the previous two. The main causes of the landslide in the study area are
mostly bedding plane dip into east which is nearly the same direction of
landslide, joint orientation, joint block systems, rotting of trees ,weathering
process and conjugate joint sets, vibration due to driving train and others
factors ;etc.
1.
Two danger zones are observed in the study area. Pyinnyaung
Formation, and weathered leucogranite are common in danger
zones. Previous retaining wall was constructed 10½ in height and
221 ft in length. Near the retaining wall, large rock blocks and
weathered rock fragmentation or rock fall are bringing down
together on the road section. This area highly weathered
Pyinnyaung Formation altered to rock fragmentation or rock fall
over these outside it. Landslide occurred both on the slope above
the retaining wall and below. Retaining wall type should be
massive gravity type or criss wall type because many rock block
and rock fall is nearly down thought on the railway road. We must
do increase of 10 ft in height 3 ft in length of the retaining wall to
26
construct according to requirements or rock fragments materials
covered by stone filled criss wall.
2.
Near the retaining wall occurred weathered leucogranite that
common with rhomb shape joint block system. Retaining wall
should be constructing of this area. The other hands, cover with
benches is useful to heavy rock block some area should be cutting
slope. Fortunately, manmade wall (a wall which is constructing
by wood, bamboo) can be constructed to protect temporarily.
3. In the unstable slope, stability is very low. Therefore, the
improving methods for stability of this slope are necessary. The
four basic methods for the stability of the slope are as follows;
(a) Reduction of slope height
(b) Reduction of slope face inclination
(c) Drainage of slope
(d) Reinforcement of slope
4.
Pyinnyaung Formation observed along the railway road from
Pyinnyaung station to Yinmabin junction. The strike of the
Pyinnyaung Formation is almost parallel to the road alignment
and dipping around 20°-60° towards the road section. Joint plane
may become slip plane. Joint plane direction indicated the
landslide direction of the rock mass and also joint plane to move
the rock mass from outcrop to the railway road. In this place, the
retaining wall should be constructed.
5.
Pyinnyaung Formation is composed of weather siltstone and hard
calcareous, conglomerate, hard thick-bedded siltstone.
Weathering processes and joint block system are prominent of
this potential area. Some area, slate and low grade metamorphic
rock are changed into very small rock fragments by weathering.
Small crib wall can be constructed of highly weathered zone.
6.
The wall may be constructed about three feet far away from the
railway road section are favorable. Rock bolt and anchor bar are
also useful of potential landslide. Oxidizing observed in the study
area. These processes are caused by weathering. These effect are
very danger to causes of landslide. One of the remark, crack can
occurred on the retaining wall because absence of water drain
27
holes. So when we construct of retaining wall, we should be
considered of this effect.
7.
Any types of retaining wall are able to apply in all slope failure.
Although the slope of this road section was serious zone, it has
become unstable recently due to the cutting of slope for widening
of the road.
8.
Mostly fair zone and stable zone are mainly located in the alluvial
plane. These area are undanger from the landslide.
9.
Stable zone was not occurred the landslide because this zone was
observed the alluvial plane and small rock exposure
10. Fair zone was found very small rock fragments which are covered
on the railway road.
11. Major joint block and unstable slope occurred in leucogranite
rock units. In this unit, concrete block wall and mesh reinforced
shortcrete have been used in this rock unit
12. The other ways for slope stability are erosion protection systems
and reinforcing systems. Erosion protection systems that protect
the slope face or toe by erosion.
13. It is needed to post skill engineers and workers in this region
support by emergency fund vehicles and laborers.
14. Among the landslide potential prevention techniques, installation
of retaining wall will be moderate cost and it has high safety
factor.
15. A new retaining wall may be constructed a new one and increased
the height and width of this retaining wall should be increased.
Acknowledgements
The author is thankful to Professor Dr. Aye Aye Myint, Head of Department of
Geology, Taungoo University, for her permission me to their research. The author is deeply
indebted to Dr.Soe Min, Assistant Lecture, Geology Department, Taungoo University, for his
helpful suggestion and encouragement. So many thanks are due to U San Win, Chairman,
Panthu Geological Service Co-operative Society, for his fruitful discussions and many useful
comments on the structural problems. Special thanks are due to Ma Ohnmar and Ma Zin Mar
Myint, M.Sc Students, Geology Department, Yangon University, for his patient assistance in
this research and computing works.
28
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environs ,Thazi Township, Mandalay Division ,Unplished M.Sc Thesis,
Yangon University,148 p.
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version), Myanmar Earthquake Committee, Myanmar Engineering Society.
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Thazi and Pyawbwe Townships. M.Sc Thesis (unpublished), Yangon
University.
29
Nwe Nwe Oo (2003) Metamorphic Petrology, Textures and Microstructures of Yinmabin
Metamorphics and Metasediments of Lebyin Group, Thazi township,
Mandalay division. Unpublished M.Sc Thesis, Yangon University.87 p.
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Townships. M.Sc Thesis, University of Yangon.
Mineral Chemistry and Assessment of P-T Evolution Based on
Thermodynamic Constraints of Metapelitic Rocks of
Thetkegyin Area, Mandalay Region
Kyi Kyi Linn1, Zaw Win Ko2 and Aung Kyaw Thin3
Abstract
Tectonic slice of pelitic schist units structurally overlying the Chaung
Magyi Group of Precambrian age are studied to deduce the P-T condition
under which these rocks were formed. Development of garnet-staurolitesillimanite schist through garnet-staurolite schist, garnet-biotite schist, and
biotite schist to chlorite schist can be continuously traceable from
structurally lower to upper part. An expected highest grade metamorphic
rock, garnet-staurolite-sillimanite schist, is analyzed by electron-probe
microanalyzer, and the analyses obtained are treated to calculate P-T
condition at which distinctive mineral assemblage of this rock have been
equilibrated. In this case the probable peak metamorphic condition is given
by thermobarometric calculation of mineral assemblage garnet + biotite +
staurolite + sillimanite + muscovite + quartz. The temperature changes
involved in this process are accurately indicated by the use of garnet-biotite
thermometry. The P-T estimates of other rock types interpreted on the basis
of characteristic mineral assemblages concerned and well-documented
petrogenetic grids, in conjunction with P-T condition yielded by
thermobarometric calculation reveal that the pelitic schist unit in this study
follows a clockwise P-T path with prograde metamorphism beginning at
~0.4 GPa/400°C and peaking at ~0.96 GPa/660°C, and subsequent
retrogression to ~0.6 GPa/476°C.
Keywords: garnet-staurolite-sillimanite schist, peak metamorphic
condition, thermobarometric calculation, prograde
metamorphism, retrogression.
Introduction
Thetkegyin area is situated at 20km northeast of the Mandalay, and the
whole research area may be regarded as the boundary zone of the Eastern
Highland in the east and the Central Cenozoic Belt in the west. Tectonic slice
of pelitic schist units structurally overlying the Chaung Magyi Group of
Precambrian age, occurring at this area are studied to deduce the P-T
condition under which these rocks were formed. Development of garnet-
1. Lecturer, Dr., Department of Geology, Yadanabon University
2. Demonstrator, Dr., Department of Geology, Panlong University
3. Associate Professor, Dr., Department of Geology, Meikhtila University
32
staurolite-sillimanite schist through garnet-staurolite schist, garnet-biotite
schist,
and biotite schist to chlorite schist can be continuously traceable from
structurally lower to upper part. An expected highest grade metamorphic rock,
garnet-staurolite-sillimanite schist, is analyzed to calculate the pressuretemperature condition under which this rock was transformed.
In early approaches the classic pelitic index minerals were qualitative
indicators of metamorphic grade (mostly temperature), and were used to
estimate the relative conditions of metamorphism across a terrane or to
compare one terrane to another. Another powerful technique based on the
work of experimental petrology is the calculation of equilibrium temperatures
and pressures from the measured distribution of elements between coexisting
phases. So far in studies of metamorphic mineral assemblages the type of
minerals present and the reactions that separate them become increasingly
aware that the compositions of virtually every solid solution phase in a
metamorphic rock varies with T and P because of exchange and continuous
reaction. The composition of the minerals involved in many of these reactions
can be sensitive indicators of the P-T conditions.
Geothermobarometry involves the calculation of temperatures and/or
pressures of equilibration (typically peak metamorphic grade) from the
measured distribution of elements between coexisting phases. In present study
Fe-Mg exchange in garnet-biotite (Ferry and Spear, 1978) is used as
geothermometer, and multiequilibrium calculations (Berman, 1991) are used
as thermobarometer, in computing all possible reactions involving the input
phases. A sophisticated activity models for many solid solution minerals is
used to estimate pressure and temperature of equilibrium which is defined by
the intersection of reactions yielded on the basis of input tables of mineral
analyses. P-T path for the pelitic schist of Thetkegyin area is modeled using
microprobe analyses of minerals present in combined with mineral
assemblages observed.
Analytical Procedures
Chemical analyses of minerals were performed on a JEOL JXA-8800R
electron-probe microanalyzer (EPMA) with three wavelength-dispersive
spectrometers at Nagoya University, Japan. In most analyses, the accelerating
voltage, specimen current, beam diameter and counting time were kept at 15
kV, 12 nA on a Faraday cup, 3 µm and 20s, respectively. A slightly defocused
33
beam of 5 µm in diameter was used for mica analyses. A representative thin
section containing mineral assemblage garnet-biotite-staurolite-sillimanitemuscovite-quartz is analyzed to calculate the pressure-temperature condition
under which this rock was transformed. Geothermobarometric calculation is
work out by using the program THERMOCALC (Version 3.26) created by
Holland and Powell (1998), and the dataset upgraded in 2003.
Mineral Chemistry
Mineral formulae for reactions and mineral abbreviations used here
follow Holland and Powell (1998). Representative analytical data for major
mineral constituents of analyzed sample are given in Appendix. Backscattered electron images for electron probe analyses are shown in Fig. (1).
Garnet
The X-ray map showing chemical profile of garnet is shown in Fig.
(2). Garnet porphyroblast occurred in this rock shows that Mg and Fe are
evenly distributed. However, Fe content is slightly higher in rim of the crystal
relative to other portion while Mg content in rim of the crystal is slightly
lower than other part. Distribution pattern of Mn content obviously changes at
the marginal portion of the garnet grain. This manner is likely to be resulted
from the effect of retrograde transformation. This assumption is supported by
comparative study on Fe-Mg exchange behavior occurred between garnet rim
and biotite developed during retrogression. The nature of selective resorption
of
Fig. 1. (a) and (b) Back scatter electron images showing analyzed minerals, and observed
mineral assemblage of garnet-staurolite-sillimanite schist. G = garnet; B =
biotite; M = muscovite; St = staurolite; Sil = sillimanite. (Loc. 22º5ʹ12ʺ
N, 96 º14ʹ34ʺ E)
34
Fig. 2. X-ray map of garnet crystal found in garnet-staurolite-sillimanite schist. Noticeable
homogeneity in distribution of chemical components can be noted.
garnet edge in retrograde process was introduced by Grant and Weiblen, 1971;
Tracy et al., 1976; Hollister, 1977 (in Tracy, 1982). In this process the product
mineral biotite is poor in Mn, and lower in Fe# = [Fe/(Fe + Mg)] than garnet.
Fe# values for garnet rim (0.92), and those for biotites (0.636 and 0.652)
support the involvement of retrogression in this rock.
Variation in Mg# = [Mg/(Mg + Fe2+)] value for the garnet crystal
involves only a little except at narrow edge of it. It implies that exchange of
Mg and Fe in this garnet is not significant. This fact indicates that this garnet
has grown within a specific P-T range.
The distribution of other components also is generally uniform throughout the
crystal. The chemical variation diagrams are illustrated in Fig. (3, and 4).
These variation patterns are typical of garnets developed at higher grade
metamorphic condition. X-ray maps showing chemical profiles of garnet
developed in garnet-staurolite-sillimanite schist and that developed in garnetstaurolite schist are shown in (Fig. 2 & Fig. 5). Both samples are from the
same stratigraphic horizon. However, they reveal the different distribution
patterns of components. In comparing the distribution pattern of these figures,
it is obvious that the chemical variation in garnet porhyroblast of garnetstaurolite- sillimanite schist is more homogeneous than that observed in garnet
crystals of garnet-staurolite schist. The chemical profiles of garnet crystals
developed in garnet-staurolite schist indicate that these garnet crystals have
developed during the prograde metamorphic condition. However, the
chemical profiles of garnet occurred in garnet-staurolite-sillimanite schist are
quite different from the profiles given by garnets of garnet-staurolite schist.
This fact in conjunction with chemical characters mentioned above prove that
35
the garnet crystal occurred in garnet-staurolite-sillimanite schist has formed
under high grade metamorphic condition (upper sillimanite zone and above,
Yardley, 1998). In this case, volume diffusion appears to be effective in
formation and/or growth of this garnet.
Biotite
Biotite occurs as matrix phase in closely associated with quartz. The K
content of this mineral is distinctly high (0.801-0.821 pfu). The Mg# =
[Mg/(Mg + Fe2+)] value is higher for biotite which is closer to the garnet
porphyroblast (0.348 to 0.364), meaning that Fe2+ lost is relatively higher than
Mg lost, and in turn giving rise higher phlogopite component.
Staurolite
Staurolite found in this rock is ferro-staurolite. It occurs as large
porphyroblast.
Fig. 3. Variation diagram showing variation characters of different chemical components
through the garnet crystal occurred in garnet-staurolite-sillimanite schist. Note that
slight changes in distribution patterns observed in all components occur at rim portion
of crystal.
36
Fig. 4. Diagram showing variation in Mg# value (Mg# = Mg/(Mg + Fe2+)) through garnet
crystal of garnet-staurolite-sillimanite schist.
Fig. 5. X-ray map showing variation of components constituting garnet crystals included in
garnet-staurolite schist.
The contents of most components are fairly homogeneous throughout the
crystal. Mg content (0.410-0.450 pfu) is low relative to Fe2+ content (3.5633.680 pfu).
Muscovite
Muscovite observed in this sample is phengitic muscovite. Si content
of this mineral is rather high (3.039-3.071 pfu). K content is high relative to
Fe2+ content.
Mineral reactions and Equilibrium Conditions
In this sample garnet and staurolite occur as porphyroblasts.
Sillimanite is found as fibrolite while biotite constitute matrix phase.
Obviously, muscovites develop at the margin of staurolite crystal (Fig. 1).
Chemical behavior of the garnet reveals that it has been formed and/or grown
37
under high grade metamorphic condition. There is no distinct inclusion phase
in garnet porphyroblast, and mineral reactions occurred between garnet and
inclusion phases are not detected. These facts indicate that this garnet crystal
has grown at a specific P-T condition, i.e., the probable peak metamorphic
condition. However, the reactions occurring between the rim of garnet
porphyroblast and the others in matrix give a clue of incident of retrograde
transformation.
Stability field of equilibrium assemblages
The activity-composition relations of minerals are calculated by the
use of the AX2 program (ver. 2.2) written by Holland and Powell (1988), and
then the activities of excess components of each mineral are used to calculate
the P-T condition for all possible reactions occurred within the equilibrium
mineral assemblage. All possible reactions are calculated using
THERMOCALC program (ver. 3.26).
The assemblage garnet + biotite + staurolite + muscovite + sillimanite
+ quartz can be used to discuss the P-T conditions at which this assemblage
developed. A number of invariant points are produced by intersection of
univariant curves along each of which distinctive equilibrium reactions
involved. The relevant stable intersection points are shown in Fig. (6). Out of
several possible reactions, the development of the garnet + biotite + staurolite
+ muscovite + sillimanite + quartz assemblage can be represented by the
following reactions.
6fst + 69cel = 8alm + 90q + 23phl + 46mu + 12H 2 O
-----(1)
186q + 23phl + 46ann + 6fst = 54alm + 69cel + 12 H 2 O
-----(2)
15ann + 6fst + 24cel = 23alm + 8phl + 31mu + 12H 2 O
-----(3)
12fst + 69cel = 23py + 16alm + 42q + 69mu + 24H 2 O
-----(4)
186q + 69phl + 6fst = 46py + 8alm + 69cel + 12 H 2 O
-----(5)
py + ann = alm + phl
-----(6)
50py + 42fst + 75mu = 56alm + 75east + 372sill + 84H 2 O
-----(7)
The vast stable intersection points defined by above reactions fall
within the pressure ranges of 0.65 GPa to 0.96 GPa, and temperature range of
550°C to 630°C (Fig. 6). Most sillimanite producing reactions yield an
equilibrium P-T condition of 0.73 GPa and 623°C. Therefore, the P-T range of
38
0.65 GPa to 0.96 GPa, and 550°C to 630° can be regarded as the highest
metamorphic condition for all equilibrium assemblages.
Mg-Fe exchange geothermometers
The formation temperature of equilibrium assemblage can be deduced
using garnet-biotite, and garnet-biotite-staurolite-muscovite-sillimanite-quartz
geothermo-barometers. Garnet-biotite geothermometer is calculated on the
basis of garnet-biotite composition. Within the pressure range of 2 kbar, it
occurs as slight changes in temperature for each reaction isograds (Fig. 7). It
means that these garnet-biotite reactions are less pressure dependent, and are
temperature sensitive. So, this garnet-biotite geothermometer can be applied
to ascertain the metamorphic temperature for this sample. This calculation
gives the temperature range of 560°C to 630°C within the pressure range of
0.6 GPa to 0.8 GPa. In figure (7) two distinct arrays of reaction curve given by
Fig. 6. P-T diagram showing relevant array
of stable intersection points arisen
from reactions took place among
mineral assemblage of garnetstaurolite-sillimanite schist.
Fig. 7. Garnet-biotite geothermometer
showing appropriate minimum and
maximum temperature, and drop of
temperature probably produced by
retrograde transformation.
reactions occurred between garnet and two analyses of biotite can be
observed. Besides, it can be noted that two curves from each group lie at
lower temperature side of diagram. These reaction curves are given by the
reactions occurred between garnet rim and biotites. This phenomenon might
be interpreted as a result of retrograde transformation. The resultant P-T
condition for retrogression deduced from garnet rim-biotite geothermometer
reaches ~0.6 GPa and 476°C. This condition might be regarded as a result of
exhumation process. The results derived from the calculation using garnet +
biotite + staurolite + muscovite + sillimanite + quartz assemblage couple with
39
the result given by the garnet-biotite geothermometer indicate that the stability
field within which present mineral assemblage has equilibrated is the
temperature range of 560°C to 660°C within the pressure range of 0.6 GPa to
0.96 GPa (Fig. 8).
Discussion
P-T condition resulted from thermobarometric calculation of garnetstaurolite-sillimanite schist is shown in Fig. (8). The relevant stability field for
all mineral assemblages is defined by tenable invariant points which are
derived from intersection of all possible univariant reactions, together with
reliable P-T condition yielded by garnet-biotite geothermometer. Certain
reactions occur within the narrow range of pressure and temperature. As
shown in Figure (8), it can be obvious that many temperature-dependent
reactions intersect some reactions which are seem to be pressure dependent,
within the pressure interval of about 1.5 kbar. Therefore, such reactions like
reaction (1) and (2) shown in this figure could be used as pressure indicators
in thermobarometric calculation.
Furthermore, the probable peak metamorphic condition could be
defined by the intersection of such reaction isograd with garnet-biotite
reaction curves used in thermometric calculation. The distinct chemical
character of garnet, i.e., fairly uniform distribution of all components from
core towards rim characterizes the growth history of garnet. The occurrences
of phengitic muscovite as well as distinct mineral assemblage (garnetstaurolite-sillimanite-muscovite) in this rock suggest that the rock formed at
higher pressure than the P-T condition for common garnet-staurolite-bearing
metamorphic rocks (Winter, 2010). The result given by geothermometric
calculation taken between garnet rim and biotites, manifests that retrograde
transformation has occurred after reaching peak metamorphic condition.
Conclusion
The comprehensive account for paragenesis of each distinctive mineral
assemblage can be established on the basis of mineral assemblages observed
in each rock
type with additional constraints provided by petrogenetic grids and P-T
condition calculated from analytical data.
The chlorite schist occupying the uppermost part of the sequence has
experienced low-grade metamorphism of lower greenschist facies condition.
From biotite schist, through garnet-biotite schist and garnet-staurolite schist to
41
condition to upper amphibolite facies condition. P-T trajectory for
development of this rock assemblage is shown in Fig. (9). However, the P-T
calculation using garnet-biotite, and garnet-biotite-staurolite-muscovitesillimanite-quartz geothermobarometer gives that the maximum P-T condition
for this rock assemblage is the temperature range of 540°C to 660°C within
the pressure range of 0.6 GPa to 0.96 GPa. Retrograssion occurred in this unit
due to exhumation process gives rise to drop of P-T condition to ~0.6 GPa and
476°C. According to facies series concept proposed by Miyashiro, 1961 (in
Bucher and Frey, 1994; Winter,2010), the sequence of metamorphic facies
encountered in the study area could be compared to the medium P/T
(intermediate pressure and intermediate temperature) facies series of
Barrovian Type.
Acknowledgement
I would like to express my sincere gratitude to U Hla Moe, Professor and Head of the
Department, Department of Geology, Yadanabon University, for his kind permission to carry
out this research work.
Special thanks are due to Dr. Zaw Win Ko, Demonstrator, Department of Geology,
Panglong University, for his kind help in getting EPMA analyses of samples from Nagoya
University, Japan, and for his suggestive discussion.
References
Berman, R. G., 1991. Thermobarometry using multi-equilibrium calculations: a new
technique, with petrological applications. Can. Mineral, 29, 833-855.
Bucher, K. and Frey, M., 1994. Petrogenesis of Metamorphic Rocks. 6th Ed., Springer-Verlag,
New York. p. 318.
Ferry, J. M., and Spear, F. S., 1978. Experimental calibration of the partitioning of Fe and Mg
between biotite and garnet. Contrib. Mineral. Petrol. 66,113-117.
Holland, T. J. B., & Powell, R., 1998. An internally consistent thermodynamic data set for
phases of petrological interest. Journal of Metamorphic Geology. 16, 309343.
Tracy, R. J., 1982. Compositional zoning and inclusions in metamorphic minerals. In Ferry, J.
M. (ed.) Characterization of Metamorphism through Mineral Equilibria.
Miner. Soc. Am. Rev. Miner. 10, 355-397.
Winter. J. D., 2010. An Introduction to Igneous and Metamorphic Petrology. 2nd Edition,
Prentice Hall, New Jersey.
Yardley, B. W. D., 1998. An Introduction to Metamorphic Petrology. Longman Earth Science
Series, Addison Wesley Longman Singapore Pte Ltd., Singapore.
42
Appendix. Analyses of garnets, muscovites and biotites in garnet-staurolite-sillimanite schist,
and calculated cation contents in (pfu) values.
G-1
G-2
G-3
G-4
G-5
G-6
G-7
G-8
G-9
SiO 2
35.53
35.15
35.20
35.64
35.27
35.46
35.27
35.38
35.42
TiO 2
0.03
0.00
0.04
0.02
0.05
0.03
0.02
0.01
0.02
Al 2 O 3
20.64
20.74
20.72
20.72
20.68
20.62
20.66
20.66
20.83
Cr 2 O 3
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
Fe 2 O 3
3.16
4.26
4.10
3.31
3.83
3.60
3.48
3.48
2.95
FeO
35.02
33.66
33.01
33.03
32.52
32.78
32.38
32.46
32.36
MnO
1.77
1.79
2.08
2.58
2.89
3.08
3.20
3.16
3.32
MgO
1.74
1.90
1.97
1.91
1.90
1.92
1.92
1.91
1.95
CaO
2.03
2.45
2.69
2.76
2.64
2.39
2.46
2.50
2.37
Na 2 O
0.00
0.00
0.01
0.01
0.00
0.01
0.00
0.01
0.03
K2O
0.00
0.01
0.00
0.00
0.00
0.00
0.00
0.00
0.00
Totals
99.92
99.96
99.82
99.98
99.79
99.89
99.39
99.57
99.25
Oxygens
12.0
12.0
12.0
12.0
12.0
12.0
12.0
12.0
12.0
Si
2.906
2.871
2.875
2.903
2.883
2.896
2.892
2.896
2.904
Ti
0.002
0.000
0.002
0.001
0.003
0.002
0.001
0.001
0.001
Al
1.990
1.997
1.995
1.990
1.993
1.985
1.997
1.994
2.013
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
3
0.195
0.262
0.252
0.203
0.236
0.221
0.215
0.214
0.182
Fe2
2.395
2.299
2.255
2.251
2.223
2.239
2.221
2.222
2.218
Mn
0.123
0.124
0.144
0.178
0.200
0.213
0.222
0.219
0.231
Mg
0.212
0.231
0.240
0.232
0.231
0.234
0.235
0.233
0.238
Ca
0.178
0.214
0.235
0.241
0.231
0.209
0.216
0.219
0.208
Na
0.000
0.000
0.002
0.002
0.000
0.002
0.000
0.002
0.005
K
0.000
0.001
0.000
0.000
0.000
0.000
0.000
0.000
0.000
Sum
8.000
8.000
8.000
8.000
8.000
8.000
8.000
8.000
8.000
Cr
Fe
43
G - 10
G - 11
G - 12
G - 13
G - 14
G - 15
G - 16
G - 17
G - 18
SiO 2
35.15
35.11
35.30
35.42
34.95
34.99
34.61
34.74
35.93
TiO 2
0.02
0.03
0.00
0.04
0.03
0.06
0.01
0.02
0.01
Al 2 O 3
20.66
20.67
20.74
20.78
20.73
20.72
20.57
20.93
20.70
Cr 2 O 3
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
Fe 2 O 3
3.63
3.87
3.61
3.65
4.59
4.30
4.73
4.92
3.25
FeO
32.30
32.04
32.36
32.34
32.03
32.67
33.15
33.48
35.72
MnO
3.16
3.36
3.26
3.19
2.92
2.34
1.94
1.89
1.80
MgO
1.91
1.91
1.91
1.97
1.94
1.93
1.90
1.92
1.70
CaO
2.42
2.41
2.43
2.51
2.63
2.64
2.23
2.08
1.87
Na 2 O
0.01
0.01
0.00
0.02
0.00
0.00
0.00
0.01
0.00
K2O
0.00
0.01
0.01
0.00
0.00
0.01
0.01
0.01
0.00
Totals
99.25
99.42
99.62
99.92
99.82
99.66
99.15
100.00
100.99
Oxygens
12.0
12.0
12.0
12.0
12.0
12.0
12.0
12.0
12.0
Si
2.887
2.880
2.889
2.888
2.858
2.864
2.853
2.840
2.911
Ti
0.001
0.002
0.000
0.002
0.002
0.004
0.001
0.001
0.001
Al
2.001
1.999
2.001
1.998
1.998
2.000
1.999
2.017
1.977
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
Fe
3
0.224
0.239
0.222
0.224
0.282
0.265
0.293
0.303
0.198
Fe
2
2.219
2.198
2.215
2.205
2.191
2.237
2.286
2.289
2.421
Mn
0.220
0.233
0.226
0.220
0.202
0.162
0.135
0.131
0.124
Mg
0.234
0.234
0.233
0.239
0.236
0.235
0.233
0.234
0.205
Ca
0.213
0.212
0.213
0.219
0.231
0.232
0.197
0.182
0.163
Na
0.002
0.002
0.000
0.003
0.000
0.000
0.000
0.002
0.000
K
0.000
0.001
0.001
0.000
0.000
0.001
0.001
0.001
0.000
Sum
8.000
8.000
8.000
8.000
8.000
8.000
8.000
8.000
8.000
Cr
44
Mus 24
Mus 25
Mus 34
Mus 35
Mus 36
Mus 38
Mus 39
Bi 27
Bi 28
SiO 2
45.68
46.60
45.96
44.57
44.35
45.19
44.95
36.78
35.10
TiO 2
0.48
0.36
0.36
0.64
0.60
0.63
0.68
2.47
2.63
Al 2 O 3
35.56
36.39
36.23
35.39
35.07
35.41
35.45
19.89
19.46
Cr 2 O 3
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
Fe 2 O 3
0.00
0.00
0.00
0.00
0.03
0.00
0.00
0.00
0.00
FeO
1.12
1.09
0.95
1.03
1.88
1.02
1.05
19.55
21.96
MnO
0.00
0.00
0.01
0.02
0.00
0.01
0.00
0.06
0.05
MgO
0.46
0.49
0.41
0.45
0.46
0.50
0.49
6.28
6.58
CaO
0.00
0.02
0.04
0.02
0.05
0.00
0.00
0.16
0.07
Na 2 O
0.78
0.82
0.84
0.81
0.79
0.77
0.77
0.18
0.26
K2O
9.96
9.94
9.74
9.83
9.48
9.81
10.09
8.41
8.11
Totals
94.05
95.72
94.55
92.77
92.72
93.35
93.49
93.79
94.23
Oxygens
11.0
11.0
11.0
11.0
11.0
11.0
11.0
11.0
11.0
Si
3.069
3.071
3.064
3.039
3.034
3.058
3.044
2.811
2.713
Ti
0.024
0.018
0.018
0.033
0.031
0.032
0.035
0.142
0.153
Al
2.817
2.828
2.847
2.845
2.829
2.825
2.831
1.792
1.774
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
Fe
3
0.000
0.000
0.000
0.000
0.001
0.000
0.000
0.000
0.000
Fe
2
0.063
0.060
0.053
0.059
0.108
0.058
0.059
1.250
1.420
Mn
0.000
0.000
0.001
0.001
0.000
0.001
0.000
0.004
0.003
Mg
0.046
0.048
0.041
0.046
0.047
0.050
0.049
0.715
0.758
Ca
0.000
0.001
0.003
0.001
0.004
0.000
0.000
0.013
0.006
Na
0.102
0.105
0.109
0.107
0.105
0.101
0.101
0.027
0.039
K
0.855
0.837
0.829
0.856
0.828
0.848
0.873
0.821
0.801
Sum
6.976
6.968
6.964
6.987
6.986
6.972
6.993
7.575
7.667
Cr
Petrogenesis of Metacarbonate Rocks Exposed in the
Nyaungwun-Malegyi Area, SinguTownship
Me Me Aung1, Than Than Nu2, Min Aung3
Abstract
The Nyaungwun-Malegyi area is situated about 44 miles north of Mandalay.
The presence of distinctive mineral assemblages such as tremolite + calcite,
diopside + calcite, diopside + forsterite + quartz in metacarbonate points out
that the study area falls within the upper limit of the greenschist facies to
the amphibolite facies. In addition, three well-defined isograds; tremolite,
diopside and forsterite isograds, are recognized. The temperature for the
first occurrence of tremolite in marble represents ~ 500°C, and that of
diopside indicates ~ 670°C. Moreover, forsterite in marble represents
forsterite-in isograd and its temperature may be reached up to about 700°C.
For detectable amount of forsterite to be developed, higher pressure
condition is required. Therefore, it can be concluded that the metamorphic
reactions occurred during metamorphism in the study area were polybaric
towards high pressure, more probably higher Pco 2 , in the course of time.
Based on the petrochemical evidences, the precursor rocks of metacarbonate
rocks for the study area are dolomitic limestone and siliceous limestone.
According to the radiometric dating, metamorphic rocks of the study area
were metamorphosed during late Eocene to Middle Miocene.
Keywords: Petrogenesis,
Isograds
Metacarbonate,
Mineral
assemblages,
Introduction
Location and Purpose of Study
The Nyaungwun-Malegyi area, the middle part of the Mogok
Metamorphic Belt (MMB), is situated about 44 miles north of Mandalay. The
location is shown in Fig (1). The main ridges comprise in the study area are
Pyingyi range and Gawuntaung.
Although there are some previous geologic accounts on the study area,
petrogenesis of igneous rocks and progressive metamorphism deduced from
mineral isograds on metamorphic rocks have not been documented yet. So,
the present research work.
1. Me Me Aung, Lecturer, Geology Department, Mandalay University
2. Than Than Nu, Professor and Head, Geology Department, Mandalay University
3. Min Aung, Director, Applied Geology Department, Yangon University
48
Fig. (1) Location map of the study area.
Regional Geologic Setting
Geologically the proposed area falls in the southern tip of the Mogok Gneisses
of La Touche, 1913, or the Mogok Belt of Searl and Haq, 1964, or the middle
part of the Mogok Metamorphic Belt of Mitchell et al., 2007. Geographically
it lies in the western margin of Shan Highland, and to the west, there is central
lowlands. The present area, the middle part of the Mogok Metamorphic Belt
(MMB), is dominated by metamorphic rocks, such as metasedimentary and
metaigneous, and associated acidic igneous rocks. They are trending N-S
with NNW-SSE strike and easterly dip of moderate to high angle. The
regional geologic setting of the Nyaungwun- Malegyi area is shown in Fig.
(2).
49
Fig. (2) Regional geological map of the study area. (source: Bender et al.,
1983)
Sequence of the Rock Units
Depending upon the lines of evidences such as field relationship,
petrography, petrochemistry, the rock sequence of the present area is
subdivided into sixteen major rock types (arrange in descending order) as
shown in table (1).
Table (1) Rock sequence of the Nyaungwun-Malegyi area
Lithologic Unit
Age
Sedimentary Unit
Alluvium
Recent
Igneous Unit
Pegmatite / Aplite
Biotite microgranite (r 1 )
Miocene
metagnanitoid
Leucogranite (r 2 )
Metamorphic Unit
Hornblende-biotite gneiss (Gn)
Late Jurassic
50
metapelite
Quartzite
Biotite schist (S 1 )
Garnet-biotite schist (S 2 )
Ordovician?
White marble (M 1 )
metacarbonates
Chondrodite-spinel marble (M 2 )
Tremolite marble (M 1 )
Diopside marble (M 2 )
Diopside calc-silicate rock (M 2 )
Spinel-phlogopite-forsterite marble (M 2 )
skarn
Forsterite- phlogopite-diopside marble (M 2 )
diopside-quartz-feldspar skarn
Wollastonite skarn
Petrogenesis of Metacarbonate Rocks
Types of Metamorphism
On the basis of textural, mineralogical and field criteria, it is possible
to distinguish two types of metamorphism that prevailed in the study area:
regional and contact. Presence of forsterite and diopside indicates the
metamorphic transformation in the present area for the whole was prograde
metamorphism, however. The contact metamorphism is evident by the
presence of skarn rocks.
Metamorphic facies
Prominent mineral assemblages in marbles and calcsilicate rocks in the
study area are (1) Calcite + graphite ± spinel, (2) Calcite + spinel +
chondrodite + phlogopite, (3) Calcite + tremolite + quartz, (4) Calcite +
diopside + quartz ± vesuvanite, (5) Diopside + clinozoisite + quartz +
plagioclase + calcite ± vesuvanite, (6) Calcite + phlogopite + forsterite +
spinel + chondrodite, and (7) Calcite + diopside + forsterite + phlogopite +
quartz. The above mineral assemblages for metacarbonates are illustrated in
ACF diagram (Fig.3).
51
A
+Qtz
+Phl
2
Spl
6
1
3
C
Cal
4
7
5
Di
Tr
Fo
F
Fig. (3) ACF diagram for mineral assemblages of metacarbonates in the study
area.
Turner and Verhoogen (1960) stated that the tremolite is the index mineral for
the greenschist facies, i.e., 300°C to 500°C and 3 to 5 kbar. In addition, the
presence of mineral assemblages Cal-Epi-Tr-Qz and Cal-Di-Epi (Pl-Qz)
indicate greenschist facies and almandine-amphibolite facies, respectively.
Winkler (1979) pointed out the mineral assemblages such as
vesuvianite + diopside and vesuvianite + epidote represent amphibolite facies
(regional medium grade).
The PTX phase relationships of dolomite rich marbles in orogenic
belts along a kyanite-type geotherm are demonstrated by Bucher and Frey,
1994 (Fig.4), and they summarized the following facts.
(1) Tremolite-bearing marbles are characteristic for the lower to middle
amphibolite facies.
(2) Diopside-bearing marbles are stable from the middle amphibolite
facies onwards.
(3) Forsterite-bearing marbles are diagnostic for granulite facies
conditions or for infiltration by H 2 O-rich fluid.
These facts are also true for the Nyaungwun-Malegyi area where
tremolite marble found in contact with diopside marble which in turn in
contact with forsterite- phlogopite-diopside marble.
It can be noted that the zonal distribution of marbles in the study area
is well agreed with Bucher and Frey, 1994’s comment. According to figure (4)
the chemical condition prevailing during the formation of above phase
relationship favors the decarbonation and decarbonation-dehydration
reactions. Therefore, it can be assumed that the metacarbonates of the study
52
area were formed in an orogenic belt where P-T condition was that of Kyanite
geotherm along with increasing Pco 2 in the course of time.
Fig. (4) PTX phase relationships in marbles along the kyanite-type geotherm.
The path (A) represents the transformation of tremolite via diopside
to forsterite for the study area. (based on the diagram of Bucher and
Frey, 1994)
Based on the works of Turner and Verhoogen (1960), Winkler (1979), Bucher
and Frey (1994) and the available information, the mineral assemblages in
marbles and diopside calc-silicate rocks designate that the metamorphism of
the study area falls within the upper greenschist facies to the amphibolite
facies.
The occurrences of distinctive mineral assemblages in skarn rocks for
the study area are (1) Calcite + wollastonite + diopside ± garnet, and (2)
Feldspar + quartz + diopside.
Winter (2010) described in the inner portion of contact aureoles,
wollastonite is created in siliceous limestones at temperature over 550°C at P
= 0.1 Gpa if Xco 2 ˃ 0.2.
Therefore, it can be assumed that the mineral assemblages in skarn
rocks represent upper limit of hornblende hornfels facies to pyroxene hornfels
facies for the study area.
53
Metamorphic Grade and Zone
The typical paragenesis, as discussed by Winter (2010), in regionally
metamorphosed siliceous dolomites is (1) talc (if Xco 2 is very low), (2)
tremolite, (3) diopside, & (4) forsterite.
The appearance of tremolite depends on the initial Xco 2 of the fluid. If
talc occurs first, tremolite should appear at ~ 480°C, diopside would appear at
~ 600°C and, forsterite would appear at ~ 690°C. (Winter, 2010)
In the study area talc does not occur, and tremolite is the first
recognizable mineral. Therefore, three distinctive mineral zones can be
recognized in marbles and diopside calc-silicate rocks: (1) tremolite zone, (2)
diopside zone and (3) forsterite zone (Fig. 5).
M1
Tremolite Zone
M2
Diopside Zone
M3
Forsterite Zone
Fig. (5) The sketch map showing the mineral zonation of metacarbonate rocks
exposed in the Nyaungwun-Malegyi Area. (Modified after MaOo,
1995)
54
Metamorphic grade in the study area is characterized by the appearance of CaMg silicate minerals, such as tremolite, diopside and forsterite.
According
to field criteria, tremolite is found in the northern part of the study area and
diopside is abundant in the central part. In addition, the pair of diopsideforsterite mineral is presented in southwestern part of the study area. On the
ground of that finding, it is inferred that metamorphic grade in the study area
increases towards the southwest (Fig. 5). The summarized petrogenetic
criteria for metacarbonates of the study area as shown in Table (2).
Table (2) Progressive mineral changes, their representative condition, reaction
isograds and petrographic significance for metacarbonates of the
study area
Epidote – Amphibolite
Greenschist
Greenschist-Amphibolite
Transition
Amphibolite
Grade
Low
Medium
High
Zone
Tremolite
Diopside or Forsterite
Diopside and
Forsterite
Representative Rock
Tremolite marble
Diopside marble
Diopside calc-silicates rock
Spl-phl-Fo marble
Fo-phl-Di marble
Reaction
Stoichiometry
(Reaction Isograd)
2Tlc+3Cal→Tr+Do
l+CO 2 +H 2 O
Petrographic
diagnostic minerals
- first appearance of
tremolite mineral
Metamorphic
condition
Facies
Metacarbonate
Calcite
Dolomite
Phlogopite
Graphite
Clinozoisite
Spinel
Tremolite
Diopside
Forsetrite
Quartz
Plagioclase
Tr+3Cal+2Qtz→5Di
+H 2 O+3CO 2
-first occurrence of diopside in the
presence of Tr, Cal and Qtz.
3Tr+5Cal→11Di+2Fo
+3H 2 O+5CO 2
- the coexistence of
diopside and forsterite
minerals
55
Isograds in Marbles and Calc-silicate rocks
Detailed geological mapping reveals three well-defined isograds;
tremolite, diopside and forsterite isograds in marbles and calcsilicate rocks.
(a)Tremolite Isograd
The first occurrence of tremolite in marble marks an excellent
mappable isograd in the field. Bucher and Frey (1994) point out that the
assemblage Tr+Tc+Do+Cal+Qz defines the tremolite-in isograd and its
temperature is about 500°C as shown in figure (6).
The reaction, Tc+Cal+Qz → Tr + CO 2 + H 2 O, as discussed by
Winkler (1979), is one of the several reactions leading to the formation of
tremolite. The stability field of parageneses, either Tr + Tc + Cal or Tr + Cal
+ Qz, from reaction depends on Xco 2 and very markedly on P (fluid) as well.
The temperature range for these parageneses is shown in isobaric T-Xco 2
diagram (P f = 5kbar) (Fig. 7).
The reaction, 5Dol+2Qz+H 2 O→Tr + 3Cal + 7CO 2 , as stated by
Winter (2010), is the tremolite bearing reaction for the large range of fluid
composition, i.e., 0.1 ˂ Xco 2 ˂ 0.87. If Xco 2 is 0.5, the tremolite would
appear at above 500°C.
According to the above criteria, the occurrence of Tr + Cal mineral
assemblage in tremolite marble represents tremolite-in isograd and its
temperature may be reached to about 500°C for the study area.
(b) Diopside Isograd
The first occurrence of diopside in dolomitic marbles defines diopsidein isograd and its temperature is about 670°C along a Kyanite-type geotherm
as shown in figure (6). (Bucher and Frey, 1994)
Winkler (1979) stated that the reaction, Tr + Cal + Qz → Di + CO 2 +
H 2 O, from isobaric T-Xco 2 diagram (Fig. 7) is believed to be of great
importance in the first formation of diopside. The equilibrium mineral
paragenesis of this reaction, Di + Tr + Cal + Qz, may therefore be of
petrogenetic significance.
Winter (2010) described that the diopside isograd in calc-silicate rocks
can be compared to the grade of sillimanite isogad in pelite. The reaction, Caamphibole + Cal + Qz → Di + CO 2 + H 2 O, leads to the form diopside from
56
dehydration of amphibole at high grade. The typical mineral assemblage is Di
+Zo + Ca-amphibole + Cal + Qz + Pgl (± Bt ± microcline).
Based on the above data, Cal + Di + Qz mineral assemblage in diopside
marbles and Di + clinozoisite + Qz + Pgl + Cal in diopside calcsilicate rocks
represent diopside-in isograd and its temperature is above 650°C for the study
area.
Fig.(6) Isograd and mineral zone
boundaries projected into the
P-T plane in siliceous
dolomites and limestones of
the study area. The green
arrow represents the reaction
path for the study area.
(Source: Bucher and Frey,
1994)
Fig.(7) Isobaric T-Xco 2 diagram at
5kb fluid pressure for
reactions in siliceous
dolomites. (Source: Winkler,
1979)
Forsterite Isograd
The favorable reaction for forsterite is Do + Di → Cal + Fo + CO 2
which takes place at 5kbar fluid pressure within a temperature range of only
35°C in response to change in the mole fraction of CO 2 . Therefore, the
equilibrium paragenesis from reaction, i.e., Fo + Cal + Di + Do, could well
serve as a reaction-isograd in the field (Winkler, 1979).
57
Bucher and Frey (1994) stated that forsterite will not form in orogenic
metamorphism of siliceous dolomitic limestone along the Kyanite-geotherm if
the system is closed. In principle, diopside will be removed from dolomitic
marbles by the reaction Do + Di → Cal + Fo + CO 2 , that replaces Do + Cal +
Di assemblage of the diopside field by Do + Cal + Fo assemblage of the
forsterite field at temperature less than 800°C with an externally derived H 2 Orich fluid, i.e. closed system marbles will be free of forsterite. In summary,
they stated that forsterite marbles are diagnostic for granulite facies conditions
or from infiltration by H 2 O-rich fluids.
The forsterite-in isograd marks approximately the same curve to the Tr
Cal-out
isograd below pressure 3kbar, as depicted in figure (6). However, at
+
higher pressure it denotes the minimum temperature for production of
petrographically detectable amounts of forsterite. It can be deduced from the
facts cited above that the occurrence of forsterite in marble is a two-way
indicator of the dolomitic character of limestone and existence of granulite
facies, at least locally, in the study area.
If the marbles are formed at open system, Cal + Phl + Fo + Spl + Chon
and Cal + Di + Fo + Phl + Qz mineral assemblages in spinel-forsteritephlogopite marble and forsterite-phlogopite-diopside marble represent
forsterite-in isograd and its temperature may be reached up to 700°C for the
study area.
Protolith
Estimation of protoliths is based on the chemical data, lithology and
structural character of the metamorphic rocks.Chemical data are obtained by
the XRF analysis from DSSTRC (Defence Service Science and Technology
Research Center) at Pyin-Oo-Lwin. The chemical analyses are given in
appendix.
Yardley (1998) expressed the appearance of whether forsterite or
diopside first in the sequence depends on the rock composition. Forsterite first
appears in silica-poor rocks while diopside appears in relatively silica-rich or
dolomite-poor rocks, and both form at very similar temperature.
The development of mineral assemblages calcite + spinel + chondrodite,
calcite + termolite, calcite + diopside + quartz, and calcite + diopside +
forsterite + phologipite + quartz indicate sedimentary carbonate protoliths. It
is substantiated by CaO-MgO-SiO 2 diagram (Fig. 8). In this diagram,
although almost all of the marbles fall within the dolomite-rich limestone
58
field, diopside marble and diopside calc-silicte rock fall within the quartz-rich
limestone field. Moreover, some distinct chemical criteria such as 4% to 19%
of MgO content in tremolite marble and forsterite-phlogopite-diopside marble,
and more than 20% of SiO 2 content in diopside calc-silicate rocks point out
dolomitic limestone and siliceous limestone for precursor rocks. According to
the above petrochemical evidences, it can be concluded that the precursor
rocks of metacarbonates for the study area are dolomitic limestone and
siliceous limestone.
Time of Metamorphism
Since the present study area falls within the MMB, the time of
metamorphism could be expressed as that of MMB. Previous workers
described the time of metamorphism for MMB on the basis of different
criteria including radiometric dating, as Eocene to middle Miocene (e.g., Mg
Thein and Soe Win, 1973; Myint Lwin Thein et al., 1990; GIAC, 1999;
Bertrand et. al., 2001; Searle et al., 2007). Therefore, it is inferred that the
time of metamorphism of the metamorphic rocks in the study area is probably
late Eocene to middle Miocene.
59
Table (3) Chemical composition of metacarbonate rocks for the NyaungwunMalegyi Area (in wt %)
Sample
No.
Rock Name
CaO
MgO
SiO 2
Locality
Mt-1
Tremolite marble
58.464
5.933
5.057
N 22o 33' 48.4" , E 96o 06' 25.4"
Mt-2
Tremolite marble
42.924
17.9
0.617
N 22o 33' 48.4", E 96o 06' 25.4"
Mt-4
Chon-Spl marble
65.086
3.27
0.18
N 22o 33' 48.4", E 96o 06' 25.4"
Mt-5
Chon-Spl marble
63.574
4.77
0.467
N 22o 33' 48.4", E 96o 06' 25.4"
Mt-9
Tremolite marble
47.754
14.43
1.9
N 22o 33' 55.0", E 96o 06' 25.8"
Mt-12
Tremolite marble
42.084
19.4
1.33
N 22o 34' 33.0", E 96o 05' 59.3"
37.506
2
25.8
N 22o 29' 26.4", E 96o 05' 00.9"
Mt-14
Diopside calc-silicate
rock
Mt-15
Diopside marble
61.292
2.52
3.39
N 22o 29' 26.4", E 96o 05' 00.9"
Mt-16
Chon-Spl marble
63.952
1.87
4.31
N 22o 28' 56.6", E 96o 05' 20.4"
Mt-17
Fo-Phl-Di marble
52.542
7.25
3.28
N 22o 28' 56.6", E 96o 05' 20.4"
Mt-18
Fo-Phl-Di marble
53.998
6.92
2.79
N 22o 28' 56.6", E 96o 05' 20.4"
Mt-19
Diopside calc-silicate
rock
39.158
2.12
20.66
N 22o 29' 29.4", E 96o 04' 51.5"
Concluding Remarks
The presence of distinctive mineral assemblages such as tremolite +
calcite, diopside + calcite, diopside + forsterite + quartz in metacarbonate
points out that the Nyaungwun-Malegyi area falls within the upper limit of the
greenschist facies to the amphibolite facies. Moreover, metacarbonates show
three distinctive metamorphic zones: tremolite zone, diopside and forsterite
zone. In addition, three well-defined isograds; tremolite isograd (represents ~
500°C), diopside isograd (indicates ~ 670°C) and forsterite isograd (represents
~ 700°C), are recognized. According to the radiometric dating, metamorphic
rocks of the study area were metamorphosed during late Eocene to Middle
Miocene.
Acknowledgement
We would like to express our gratitude to Dr. Myint Thein, Rector (Retd.), Sagaing
Institute of Education, for his invaluable advice and suggestions and for comments.
60
References
Bender, F., (1983). Geology of Burma. Beiträäge zur regionalen Geologie der Erde n°16.Berlin, Stuttgart, 293p.
Bertrand, G., Rangin, C., Maluski, H., and Bellon, H., The GIAC Scientific Party, (2001).
Diachronous cooling along the Mogok Metamorphic Belt (Shan Scarp,
Myanmar): the trace of the northward migration of the Indian syntaxis.
Jour. Asian Earth Sciences 19, 649-659.
Bucher, K., and Frey, M., (1994). Petrogenesis of Metamorphic Rocks. 6thed., Springer
Verlag.
GIAC, (1999). The Tectonics of Myanmar: final report, GIAC Project. 1996-1999.
La Touche, T.H.D., (1913). Geology of the Northern Shan State.Memoirs of the Geology
Survey of India, 39, (2).
Ma Oo, (1995). Geology of the Ngwedaung-Male Area, Singu Townships. (Unpublished
M.Sc Thesis, University of Mandalay)
Maung Thein and Soe Win, (1973). The Meamorphic Petrology, Sturcture, and Mineral
Resources of Shantaung- U-Thandawmyet Range, Kyaukse District, Burma
Jour.Sci. Tech., 3, 487-514.
Mitchell, A.H.G., Myint Thein Htay, Kyaw Min Htun, Myint Naing Win, Thura Oo, Tin
Hlaing, (2007). Rock relationships in the Mogok Metamorphic Belts, Tatkon
to Mandalay, central Myanmar. Jour. of Asian Earth Sciences, 29 (2007),
891-910.
Myint Lwin Thein, Ohn Myint, Sun Kyi & Hpone Nyunt Win, (1990). Geology and
stratigraphy of the metamorphosed early Paleozoic rocks of the MogokThabeikkyin-Singu-Madaya Areas. Staff Report No-98.
Searle, D.L. and Haq, B.T., (1964). The Mogok Belt of Burma and its relationship to the
Himalayan Orogeny. 22nd. Internal. Geol. Congr. India, 11:133-161.
Searle, M.P., Noble, S. R., Cottle, J.M., Waters, D.J., Mitchell, A.H.G., Tin Hlaing,
Horstwood, M.S.A., (2007). Tectonic evolution of the Mogok metamorphic
belt, Burma (Myanmar) constrained by U-Th-Pb dating of metamorphic and
magmatic rocks. Tectonics, 26.
Turner, F. J. and Verhoogen, J. (1960). Igneous and Metamorphic Petrology. 2nd ed. Mc GrawHill, New York.
Winkler, H.G.F., (1979). Petrogenesis of Metamorphic Rocks.5
Heidelberg Berlin.
th
ed., Springer-Verag, New York
Winter. J. D., (2010). An introduction to igneous and metamorphic petrology. 2nd ed., Prentice
Hall, New Jersey.
Yardley, B.W.D., (1998). An introduction to Metamorphic petrology. Addison Wesley,
Longman Singapore pte Ltd.
Volcanic rocks, Ultramafic rocks and its related
Serpentinization of Maingna-Naungnan-Alam Area, Myitkyina
District, Kachin State
Hnin Min Soe
Abstract
The Maingna-Naungnan-Alam Area is situated in the Myitkyina District,
Kachin State. This study area is mainly composed of ultramafic rocks
(harzburgites, lherzolites, serpentinized harzburgites, serpentinized dunites
and serpentinites), basic rocks (dolerite dykes) and acid volcanic rocks
(dacites, rhyolites and volcanic tuffs). The present work deals with the
serpentinization of ultramafic rocks. The present ultramafic body is
included in the he Eastern Ophiolite Belt of Myanmar and falls within the
Alpine type. In the study area the plutonic (ultramafic) rocks of the
Inkhaing Bum can be regarded as incomplete or dismembered ophiolite
suite due to the missing upper portion of the typical ophiolite sequence.
Serpentinites of this area are divided into three categories namely (1)
Massive serpentinite (Type I) (2) Sheared-serpentinite (Type II) and (3)
Vein serpentinite (Type III). Degree of serpentinization is early to advanced
stage. Common serpentine minerals are antigorite, lizardite and chrysotile
with minor magnetite, chromite and brucite. The age of emplacement of the
ultramafic body is postulated as Jurassic. Later or at the same time,
serpentinization took place and volcanic extrusion may be formed
simultaneously.
Keywords: Ultramafic Rocks, Dismembered
Serpentinization, Jurassic.
ophiolite
suite,
Introduction
Location, size and accessibility of the area
The study area is situated in Myitkyina District , Kachin State, about 6
miles northeast of Myitkyina . This area is bounded by Latitudes 25˚ 23´ 30̋ N
to 25˚ 37´ N and Longitudes 97˚ 26´ E to 97˚ 30´E in one-inch topographic
maps, 92 G- 6,7,10 and 11. It is about 12 miles long and 5 miles wide. It
covers an area of approximately 60 square miles. It can be easily reached by
car from Myitkyina (Fig.1).
1. Lecturer, Dr., Department of Geology, Yadanabon University
2. Demonstrator, Dr., Department of Geology, Panlong University
3. Associate Professor, Dr., Department of Geology, Meikhtila University
62
97 30
97 15
ka
-H
-in
97 45
Mali-Hka
ng
pu
Tanphre
H
May-Hka
25 45
Ayeyarwady River
Alam
25 30
Manhkring
Pyidaung
Myitkyina
Maingna
Blaminhtin Bridge
Pamati
Waimaw
Washawng
Katcho
0
4 mil es
25 15
Fig.1 Location map of the study area.
Purposes of the study area
The principal objectives are:(1) To prepare a geological map of the area.
(2) To subdivide the rock units of the research area.
(3) To describe the serpentinization of ultramafic rocks.
Method of study
As conventionally done in regional geologic mapping, both field and
laboratory methods were applied. Two-inch topographic map enlarged from
one-inch topographic map, a brunton compass, a geological hammer and a
(10X) pocket lens were used in the field. The location of the outcrops was
made by intersection methods and the field observations were mainly confined
to stream sections, cart-tracks, foot-paths and ridge-crests. Indirect geological
information such as the type and intensity of vegetation, soil tone, differential
weathering patterns and other available geological evidences were utilized in
places of poor rock exposures. The contact lines between different rock units
were plotted on the map by using the data mainly from field observations and
partly from aerial photographs.
63
Rock Types and Distribution
I Ultramafic Igneous Rocks (Inkhaing Bum Ultramafic Rocks)
Name Derivation
The ultramafic rocks exposed at Inkhaing Bum about ( ) are here
referred to as the Inkhaing Bum ultramafic rocks.
Distribution and Lithology
The ultramafic rocks (harzburgites, dunites, serpentinized
harzburgites, serpentinized dunites and serpentinites) cover the whole
Inkhaing Bum. They occur as semicircular, bold massive outcrops showing
the pitted nature and sheeted joints (Figs. 2 & 3). Both fresh and weathered
color of this rock is dark green to bluish black. The rock is a soft, soapy
variety. Frequently it is traversed by narrow vein-lets of light green chrysotile
veins. An outcrop of totally serpentinized outcrop without any trace of the
original parent rock is exposed at lower elevation of Inkhaing Bum
(Grid.193695).
Fig.2 Weathered ultramafic rock
showing pitted nature
(Grid. 194680).
Fig.3 Bold massive ultramafic body
showing the sheeted joints
(Grid. 185670).
Contact relationship and Age
The contacts between rock units were not found due to the thick red
soil cover.
The age of the emplacement of ultramafic rocks is Jurassic (Mitchell,1979).
64
Acid Volcanic Rocks
Hmanpya Taung Dacite
Name Derivation
The rock unit is named after the Hmanpya Taung about (1459ʹ) about
2 miles east of the Balaminhtin Bridge. It is about 1.5 miles long and 1 mile
wide. It is mainly composed of dacite.
It is exposed mainly at Hmanpya Taung. This unit is highly altered and
weathered. It displays massive outcrops (Fig.4), reddish brown to dark brown
colors on weathered surface and whitish pink to chocolate brown on fresh
surface. It is composed essentially of phenocrysts of feldspar, quartz and
biotite with minor amounts of other very fine-grained minerals in the matrix.
This dacite is oxidized under humid condition producing red earth soil. This
unit is also called reddish brown dacite.
The contact between the reddish brown dacite and volcanic tuff is
defined by the fault (different elevation of ridges, rock units and aerial
aerialphoto interpretation). Chilled zone is not found due to thick red soil
cover. The age of Hmanpya Taung dacite may be the same as that of the
Inkhaing Bum ultramafic rocks but may be a different phase.
Fig.4 Massive outcrop dacite showing reddish brown color at Hmanpya
Taung (Grid. 235530).
65
Singaung Taung Dacite
Name derivation
This unit is named after the Sigaung Taung (1824ʹ). It is well exposed
at Singaung Taung.
It is well exposed at Singaung Taung and in the southern part of the
Naungcho Taung. They occur as dome-liked hills (Fig.5). It displays dark grey
to yellow grey on weathered surface and whitish grey to bluish grey on fresh
surface. It is mainly composed of phenocryst of feldspar, quartz, biotite and
laths of plagioclase and other very fine-grained minerals in the matrix.
The contact between the dacite porphyry and volcanic tuff is faulted in
the southern part. These dacite porphyry and rhyolite are also faulted contact
too in the western part. Sharp contact is not found due to thick soil cover. The
constituent minerals of Sigaung Taung dacite are less altered and weathered
than those of Hmanpya Taung dacite. Thus, Sigaung Taung dacite may be
formed at the same age as Hmanpya Taung dacite but may be a later phase.
Fig.5 Photograph showing dome-shaped hill of Naungcho Taung (Grid.
214569).
66
Tayoke Taung Rhyolite
Name derivation
there.
It is named after Tayoke Taung (1451ʹ) because it is well- exposed
This unit is exposed mainly at Tayoke Taung (Loi-ho-pai) about 2
miles long and 1.5 miles wide. It is dark grey to grayish brown color on
weathered surface and white to whitish pink on fresh surface. Layerings of
lava are common features of this rock unit (Fig.6). It is composed of alkali
feldspar, quartz and other fine-grained minerals in the matrix. Most rhyolites
are silicified.
In the east of the Tayoke Taung rhyolite, there is a wide valley which
may be faulted contact by the aerial photographic interpretation. Rhyolitic hill
is lower in elevation than dacite hill (aerial photographs, topographic maps
and in the field) The age of the rhyolite is the same as that of Singaung Taung
dacite but may be a later phase due to the less alteration degrees in this unit.
Fig.6
Massive outcrop rhyolite showing layer of lava flow at Tayoke Taung,
(Grid. 186560).
67
Volcanic Tuff
Name Derivation
tuff.
It is mainly composed of crystals and glass, so it is named as volcanic
It is exposed between Singaung and Hmanpya Taungs and along the
cart-track of Kwituo road. It displays whitish yellow to whitish grey on
weathered surface and white to whitish pink on fresh surface. It is composed
essentially of glass and crystals. Layering is very conspicuous on the surface.
This hill is lower in elevation than surrounding hills. The formation of
adjacent units (dacite and rhyolite) are earlier than the volcanic tuff due to the
intense alteration degrees found in the above two units. Therefore this unit
may be younger than the dacite and rhyolite. Eruption center can not be
determined.
Dyke Rocks
Dolerite dykes are common in the present area. The dolerite dykes
formed along the Ayeyarwady River, also intruded to the volcanic tuff and
ultramafic body and cropout at south-eastern part of Inkhaing Bum. They
occur as small bodies separated from the Inkhaing Bum ultramafic body. They
are light grey to dark grey on fresh surface. Time of emplacement of this unit
is the end of plutonism and volcanism. So it is the youngest unit in the study
area.
Recent gravels and Alluvium
Alluvial deposits are exposed along the east and west banks of
Ayeyarwady River and occupy one-third of the area. The deposits include
sands, silts, clays and some placer deposits. The gravel deposits are found
along the river and stream channels. These deposits are composed of cobble to
boulder size diorite, dacite, rhyolite and other igneous rocks. Distribution of
rock units is shown in the geological map (Fig.7).
68
J
E
Inkhaing Bum
72
EXPLANATION
Qal
74
Alam
2885'
70
Qal
J
D
Lamongzup-hka
68
Lamongzup
Taung
ToD
ToD
D
showing layers and intruded by dolerite dykes
Acid Volcanic Rocks
Tayoke Taung Rhyolite: sheeted nature
J
and massive boulder. Fine-grained
hypocrystalline texture.
Qal
J
64
1
Qal
62
Naungnan
J
60
Singaung Taung
F
D
58
J
D
B
56
1824'
J
Kwitu Taung
D
54
Hmanpya Taung F
52
Naungcho
Taung
50
18
16
F
JT D
1
J
Qal
1500
2
A
J
1
1
22
20
2
Singaung Taung Dacite: fine-grained
porphyritic texture.Quartz,orthoclase and
alkali-feldspars are present.
Hmanpya Taung Dacite: reddish brown
colour, quartz, orthoclase and plagioclase are
essential minerals. Alteration degree is high.
Inkhaing Bum Ultramafic Rocks
C
F
D
J
1
1
J
Tayoke Taung1451'
Dyke rocks: dolerite dyke showing
porphyritic texture
Pyroclastic Rocks
Volcanic Tuff: crystal tuff and victric tuff:
JT
1583'
66
SEDIMENTARY UNITS
Alluvium: gravel, sand and silt
Unconformity
IGNEOUS UNITS
Serpentinite: pseudomorphic,non-pseudomor
-phic textures and vein serpentine associated eless altered ultramafic rock such as harzburgite,
serpentinized harzburgite and serpentinized dunite.
24
1 miles
0
CROSS-SECTION ALONG A-B
Geologic Symbols
J 2
0
A
Fault [certain]
Fault [uncertain]
Kwitu Taung
JT
Stream
River
Bridge
Motorable road
Village
Contact
Hmanpya Taung [1500]
Toyoke Taung [1451']
3000
Geographic Symbols
J
D
B
Dyke
High point
Asbestos
CROSS-SECTION ALONG C-D-E
Inkhaing Bum Taung[2885']
Singaung Taung[1824] Ayeyarwady River
Horizontal scale - 2 inches = 1 mile
Lamongzup Taung[1583']
J
Qal
J 1
ToD
Vertical scale - 1 inches = 3000 ft
3000
C
D
E
HNIN MIN SOE , 1999
FIG.7 GEOLOGICAL MAP OF THE MAINGNA-NAUNGNAN-ALAM AREA,
MYITKYINA DISTRICT, KACHIN STATE
69
Serpentinization
There are three types of serpentinization resulting in the serpentine
types I, II and III in the study area. Under microscopic study, the following
features are found and they are also characteristic of the Alpine-type
serpentinite association (Hess, 1955, Thanyar, 1960).
(1) Accessory chromite is present in every thin section.
(2) Anhedral grains of olivine and orthopyroxene are predominant.
(3) Feldspar is totally absent in all thin sections.
(4) The MgO / FeO ratio is relatively high. (i.e.olivine and orthopyroxene
composition respectively lies in the forsterite and enstatite-bronzite
ranges.).
Serpentine minerals are mainly of antigorite, lizardite, and chrysotile.
Chromite, magnetite and brucite occur in minor amounts. Microscopic
textures are used as an aid to differentiate these minerals according to Wick
&Whittaker (1977) in Table (1).
Table.(1) Summary of eight types of serpentinization (Wick and Whittaker,
1977).
Type
Condition
-Falling T
of sub-stres
1 -absence
shearing
-nucleation of antigorite
-Falling T
-presence of sub-stres
2 shearing
-Falling T
-absence of sub-stres
3 shearing
-Falling T
of sub-stres
4 -absence
shearing
Texture
Mineral comp. Region
Remarks
Fracturing-falling veins with this
type will be composed of antigorite
Pseudomorphic tex.
Antigorite
A
Foliated non-pseudomorphictex.
Antigorite
A
Lizardite
B
Chrysotile does not usually occurs in abundance
Lizardite + Brucite
C
joint planes with or without lizardite and brucite.
C
With or without lizardite and chrysotile
+/- brucite veins
Pseudomorphic tex.
Foliated non-pseudomorphictex. Chrysotile +/- Brucite
-no nucleation of antigorite
pseudomorphic, but may occur in veins along,
Chrysotile asbestos veins associated e- non asbestiform
-Recrystallization of pseudomorphic tex. Lizardite + Brucite
-Rising T
5 -absence of shearing
Relic primary minerals to form Chyysotile-brucite+/- B&C non asbestiform veins of chrysotile, not infrequently
of the Povlen-type, or lizardite+/- brucite commonly
-no nucleation of antigorite non-pseudomorphic.
Lizardite
form in association with these textures.
-Rising T
Foliated non-pseudomorphic
Chyysotile-lizardite
6 -presence of shearing
B&C
Less
frequently multilayered lizardite+/- brucite
+/-brucite
-no nucleation of antigorite texture & vein
-Rising T
7 -presence of shearing
-Rising T
8 -absence of shearing
-Recrystallization of type 3 tex.
-Previously serpentine mineral give
Antigorite+/- brucite
non-pseudomorphictex.
-Crude pseudomorphic tex.
B&C
Foliated non-pseudomorphict tex. Antigorite+/- brucite
A
70
Type I Serpentinite
This is blocky massive type and occurs in inner part of the ultramafic
body especially at (Grid. 170702).This type was caused by circulation of
ground water. Development of this type is marked by an absence of
substantial shearing. In this type the chief mineral is lizardite and antigorite
with minor brucite, magnetite and chromite. In outcrop, serpentinites after
dunite and after harzburgite have a distinct character. This type is located in
the southern part of the Inkhaing Bum especially at (Grid. 170725).
Microscopic study: Serpentine replace spaces along the cracks of olivine
(Figs.8 & 9). A pseudomorphic (mesh) texture is more predominant than nonpseudomorphic textures. In mesh texture two portions may be considered,
mesh rims and mesh centre. Most of the mesh rims are composed of lizardite.
Mesh centres have usually relict olivine and if, isotropic mesh centre can be
noted as lizardite with brucite (Fig.10). Non-pseudomorphic textures of
interpenetrating and interlocking textures are minor. Magnetite is mostly
found within the mesh rims of antigorite as string patterns. This type of
serpentinization is possibly type 1 of Wick &Whittaker (1977) in region A.
Fig.8 Serpentinized harzburgite with serpentine minerals along the cleavage
of othopyroxene and cracks of olivine in type I (Grid. 185670).
Fig.9 Parallel vein and mesh pattern of serpentine replace along the cracks
of olivine in type I (Grid. 170725).
Fig.10 Pseudomorphic texture showing olivine mesh centre & isotropic mesh
centre & lizardite mesh rim in type I (Grid. 194680).
Volume Expansion: Less expansion by emplacement of serpentine within
cracks of olivine, magnetite or chromite, alteration of magnetite to goethite
and expansion in antigorite.
71
Degree of serpentinization: Degree of serpentinization is moderate to
advance.
Degree of serpentinization is judged by the presence of magnetite,
their nature and textures. During early stages, magnetite is found as discrete,
fine-grained. When the degree of serpentinization increases magnetite is found
as mesh centers, small disseminated grains. And in the advanced stage,
magnetite is present in fairly amounts and in granular form.
Possible Original Rocks: Orthopyroxene and relict olivine indicate that the
type I is derived from both dunite and harzburgite.
Type Ii Serpentinite
Type II was developed by tectonic stress, along fault zones. They are
occurred as vertical cliffs. This type is marked by its smooth shining surfaces.
This type is located in the southeastern part of Inkhaing Bum especially at
(Grid. 205705) and Alam village.
Microscopic study: Type II serpentinite is composed mainly of antigorite
with lizardite, chrysotile and bastite in minor amounts. In these rocks
hourglass textures, combination with interpenetrating or interlocking texture
are recognized. Hourglass texture is the most predominant (Fig.11). Slipfibres (chrysotile) pass through antigorite (Fig.12) and antigorite occurs as
pseudomorph after pyroxene (bastite) (Fig.13). Magnetites are seen as
disseminated grains in the hourglass texture. Based on these facts, (presence
of shearing, and nucleation of antigorite), the type of serpentinization is
possibly type 6 of Wick &Whittaker (1977) in region B-A.
Volume Expansion: By brucite is recognized and olivine grains are replaced
by serpentine minerals. Expansion occurred in single chromite fractures filled
by serpentine minerals (Fig.14).
Degree of serpentinization: Moderate to advanced stage is predominant. All
minerals are altered to serpentine during advanced stage.
Possible Original Rocks: Relict olivine, orthopyroxene and a few
clinopyroxene minerals indicate that this type may be derived from
harzburgite.
72
Fig.11 A common hourglass textures with interpenetrating texture in type II
(Grid. 219743).
Fig.12 Chrysotile (slip-fibre) vein passing through antigorite bastite in type II
(Grid. 215710).
Fig.13 Antigorite occurs as pseudomorph after pyroxene (bastite) in type II
(Grid. 205705).
Fig.14 Single grain chromite occurs in pseudomorphic texture in type II
(Grid. 205705).
Type III Serpentinite
Type III was resulted from cracking and jointing of pyroxeniteperidodite which facilitated access for mineralizing solution. This type is
located in the southwestern part of Inkhaing Bum especially at (Grid.
145689).
Microscopic study: Pseudomorphic textures and dislocated chrysotile
veinlets indicate post serpentine deformation. Serpentine veins are mainly
composed of chrysotiles and pinching, branching and swelling are common in
chrysotile veins (Fig.15). Aggregates of lamellar flakes of antigorite and
chrysotile vein occur in this type (Fig.16). Recrystallization features, serrated
veins (Fig.17) are often found and asbestos (chrysotile) veins cut aross along
fracture of chromite grain (Fig18). Small disseminated magnetite occurs at the
boundaries of chrysotile veins. Asbestos is also locally economic important in
Inkhaing Bum area. The type of serpentinization is possibly type 5 of Wick
&Whittaker (1977) under condition of B and C.
Volume Expansion: in this type volume expansion features are not found
unlike the type I and II serpentinites.
Degree of serpentinization: in this rock unit, degree of serpentinization is
early to advanced.
73
Possible Original Rocks: the original rock unit which the veins cut is dunite
and harzburgite.
Fig.15 Chrysotile veins showing pinching, branching and swelling in type III
(Grid. 145689).
Fig.16 Photomicrograph showing aggregates of lamellar flakes of antigorite
and chrysotile vein in type III (Grid. 165683).
Fig.17 Serrated chrysotile vein in mesh texture serpentine in type III (Grid.
155669).
Fig.18 Chrysotile vein cutting along fracture of chromite grain in type III
(Grid. 150683).
Processes of Serpentination
In the study area, there are two original major rock types, dunite and
harzburgite; they are partially to wholly altered to serpentinites and the
required water for serpentinization was brought into the mass from the
surrounding country rocks.
2Mg 2 SiO 4 + 3H 2 O
Mg 3 Si 2 O 5 (OH) 4 + Mg(OH) 2
(Forsterite) (Vapour)
(Serpentine) + (Brucite)
Dunite is altered to Serpentine +Brucite+ Magnetite
Olivine + H 2 O
Serpentine +Brucite+ Magnetite
Harzburgite is altered to Serpentine + Brucite + Magnetite
Olivine + Orthopyroxene
Serpentine + Brucite + Magnetite
74
4-8
Earth pressure & temperature
-7
3-6
V
P+V= B
1-2
IV
E+Q+V=T
-3
III
E+V= T+F
P, Kb
II
T+V= S
2-4
I
Depth in miles
F+V= S+B
-5
-1
Liquid
Vapour
300
400
500
W= Water vapour
600
T HC
700
800
900
P = Periclase
B= Brucite
Q= Quartz
E= Enstatite
S= Serpentine
F= Forsterite
T= Talc
Fig.19 Pressure-temperature curves of univariant equilibrium in the system
MgO-SiO 2 -H 2 O (after Bowen & Tuttle, 1949).
At pressure below 1 kb, brucite + serpentine develop from forsterite in
the presence of water vapour at 400 HC. Talc is found in the study area, so,the
temperature of serpentinization was probably between 400 HC to 500 HC. The
univariant equilibrium curves established by Bowen & Tuttle ,1949 (Fig.19)
was used.
Age of rocks in the study area
The age of ultramafic body was recorded as Jurassic according to
Mitchell (1979). For the lack of assumed evidence for determining the age of
75
the ultramafic body and according to some works (Clegg 1941 and IGCP
National Committee 1982), the present study considers the age of ultramafic
as the Mesozoic. However, some radiolarian sample at Myitson area was
determined as Jurassic by Hla Htay, 2006 (Fig.20). It was supported by the
UNDP project in which K/Ar radiometric age determination on hornblende
from a pegmatite gabbro veins within a serpentine boulder at Ma-U Chaung
area indicates 158 +/- 20 my which is Middle Jurassic (Mitchell et.al, 1979).
Fig.20. Radiolarian fossil from chert unit at Myitson area (Hla Htay,
2006).
The emplacement of the present ultramafic body can be postulated as
the ultramafic rocks were squeezed upward into flysch in the Jurassic time by
the effect of intense folding, protrusion and regional thrusting of orogenic
movement (Mitchell,1979 and Colemen, 1977). Initially, they may have been
heated resulting in some degree of metamorphism near their body. However,
it is believed that final movement of its body into present position was as
pushed up cold body by tectonic movement. Later or at the same time,
serpentinization took place especially at the boundaries of ultramafic body
facilitated by sheared movement.
At the same time partial melting took place in the subducted oceanic
mantle, and the extrusion of this partial melt formed the volcanic arc, where
the volcanic rocks were formed. The eruption of these volcanic rocks in the
study area was a fissure-type due to faulting.
We can use the Miyashiro’s Paired-Metamorphic Belt model,
serpentinites and acid volcanic rocks encountered together in the area
investigated. The occurrence of jadeite and glaucophane schist in the adjacent
Jade Mine Area represents a high-pressure metamorphic belt while the Mogok
76
Belt, lying parallel to the former represents a low pressure metamorphic belt
in the east (Maung Thein,1983 and Nyan Thin,1991).The sediments
characteristic of melanges and ophiolites were exposed along the major thrust
sheets (Kyaw Win and Thit Wai,1971) in the trench zone forming the
approximately central parts of the main Rakhine Yoma-Chin Hills proper in
the west. They indicate that the rocks in the study area might have been
formed by subduction accompanied by obduction in the subduction zone as
the Oceanic (India) plate collided with continental (Eurasian) plate. Therefore,
the age of acid volcanic rocks may be the same time as ultramafic rocks.
Ophiolite suite of the study area
The present study area is included into the Tagaung-Myitkyina Belt or
Eastern Ophiolite Belt (Fig.21). It is situated along the western rim of SinoBurma Range extending from, Sumprabum in the north, through Myitkyina
area and Bhamo to Shwegu and Tagaung in the south. The follow facts favor
this situation according to Coleman (1977), Hutchison (1975) and Bender
(1983).
(a) Ultramafic rocks are partially to wholly transformed to
serpentinites. However, the original rocks are mainly harzburgite
(pyroxenite-peridodite), a kind of pyroxene -peridotite which
forms the basal part of a typical ophiolite sequence transformed
from the upper mantle.
(b) Chromite grains are found in serpentinized harzburgite and
serpentinized dunite. They are also the basal part of typical
ophiolite sequence.
(c) A prominent diabase (dolerite) dyke has been found in the study
area particularly (grid; 185665). It is also the middle part of a
typical ophiolite sequence.
(d) Predominance of magnesium-rich olivine over pyroxene.
(e) Presence of progressive serpentinization in harzburgite and
dunite.
(f) On a regional scale, thrust fault is present along the eastern
boundary of the Inkhaing Bum ultramafic body dipping toward
west.
(g) Lack of a widespread contact metamorphic aureole.
In the present study area basal and middle portion of a typical ophiolite
suites can be observed. But beyond the study area, at May-hka and Mayli-hka,
77
the upper portion of the ophiolite suite, such as bedded chert and greywacke
can be found. Therefore, the ultramafic rocks in the research area are part of
ophiolite suite due to the missing of the upper portion of the typical ophiolite
sequence.
Fig.21 Map showing the ophiolite belts of Myanmar.
In the cross-section of an ophiolite suite (Fig.22), the top of the
ophiolite sequence consists of fine-grained, ocean sediments (cherts,
limestones, etc.). Below this are pillow basalts, which form when hot magma
is extruded onto the ocean floor. These rocks are often extensively altered by
interaction with seawater. Sheeted or intruded dikes occur below the pillow
basalts. These dikes represent the feeders to the subaqueous pillow basalts,
and typically intrude consecutively into one another before cooling is
complete. Underlying the basalts is a layer of its intrusive equivalent gabbros. The upper part of the gabbros is typically not stratified, but the basal
part of the gabbros commonly contains cumulate layers. The Cumulates were
the first formed crystals which sank to the base of the chamber.
The base of the gabbro layers, where the cumulate gabbros pass into
an ultramafic cumulate, marks the geophysical base of the crust known as the
78
Moho. Here the density contrast causes a marked attenuation in seismic
velocity. The petrological contact between the earth's crust and the mantle lies
at the base of this ultramafic layer. The harzburgite layer at the top of the
mantle is considered "depleted" - it is composed of only orthopyroxene and
olivine, and lacks the typical clinopyroxene and spinel of the underlying
fertile mantle rocks (lherzolite).
Fig.22 Idealized cross-section of an ophiolite suite.
Economic Aspects
The interesting mineral deposits in the study area are placer gold,
asbestos, decorative stones and construction materials. The placer gold is
concentrated in the gravel beds along the Ayeyarwady River and stream
sections. The gold explorations are done extensively along the Ayeyarwady
River in summer and winter times. Local people operate the gold by hand
panning. The gold grain size ranges from small nuggets to dust. Asbestos can
be observed at (Grids.150681, 141689 & 141712), Pa-La-Na production area.
They are situated in type III serpentinite area. The color of chrysotile fibre
(asbestos) is white and yellowish green. It is suitable for cement roofing
79
production. Serpentinite can be used as decorative stones due to their
attractive yellowish green to deep green color with sub-vitreous luster.
Rhyolite and dacite in the study area can be used as sources of concrete
aggregates and road materials. Sands and gravels along Ayeyarwady River are
used as construction materials.
Results
A geological map of the virgin area (Maingna-Naungnan-Alam
Area, Myitkyina District, Kachin State) was also attempted (Fig.7). Based on
the mineral composition, the precise nomenclature of both the acid volcanic
and ultramafic igneous rocks were described. The present work emphasizes on
the serpentinization of the ultramafic body. According to the field observation
and laboratory work, the serpentinization taken place in the ultramafic rocks
(dunite and harzburgite) of the Inkhaing Bum, can be divided into three types.
Type I serpentinite was mostly found in the inner part of the ultramafic body,
Type II occurs only along faults and Type III was found in the outer part
ultramafic body. The common serpentine minerals are antigorite, lizardite and
chrysotile with minor magnetite, chromite and brucite.
Discussion
After the studying the rock types of the research area ultramafic and
acid volcanic rocks were encountered together in the area investigated. The
emplacement of ultramafic body was recorded as Jurassic. Thus, highpressure, low-temperature type ultramafic rocks in the west of the study area
and high- temperature, low- pressure type volcanic rocks in the east were
simultaneously formed. Therefore, the age of acid volcanic rocks in this area
may be Jurassic. Serpentinization took place later or at the same time as
ultramafic units.
Conclusion
From the research work the following conclusions have been reached.
1. Rock types such as acid volcanic rocks (rhyolites, dacites & volcanic
tuffs), ultramafic rocks (harzburgites, dunites, serpentinized
harzburgites, serpentinized dunites and serpentinites) and basic rocks
(dolerite dykes) were observed.
2. Under microscopic study, chromite grains, anhedral grains of olivine
and orthopyroxene, high ratio of MgO / FeO, absence of feldspar in
all thin sections, pseudomorphic (mesh) textures, non-
80
pseudomorphic textures of interpenetrating and interlocking textures
and common serpentine minerals were observed.
3. The ultramafic body, diabase dykes and chromite grains were
members of a typical ophiolite sequence. However, in this research
area a sequential order of a typical ophiolite suite cannot be observed
possibly due to the subduction zone tectonic movements. Therefore
it can be regarded as incomplete or dismembered ophiolite due to the
missing upper portion of the ophiolite sequence in the study area.
But beyond the study area, at Myitson, the upper portion of the
ophiolite suite can be found.
4. Degree of serpentinization for study area is early to advanced stage. A
probable condition for serpentinization is postulated as at pressure
below 1kb, temperature of 400 HC to 500 HC depending on the
mineral assemblages. Time of emplacement of ultramafic rocks is
Jurassic; later or at the same time serpentinization occurred.
5. The economically important mineral deposits in the study area are
placer gold, asbestos, decorative stones (serpentinites), road
materials (rhyolites and dacites) and construction materials (sands
and gravels).
In conclusion, the research work is emphatically meant to stimulate the
interest of the future workers for improving the current findings with better
expositions.
Acknowledgement
Special appreciation is expressed here for valuable advice and close supervision by
U Tun Aung, my M.Sc program supervisor, Head Master of Yenanchaung College (Retired)
for his encouragement and giving the fruitful suggestions and guidance.
References
Bender, F.,(1983): Geology of Burma. Gebruder Borntraeger Berlin, Stuttgart. P.239.
Bowen, N.L., & Tuttle, O.F.,(1949):The system MgO-SiO 2 -H 2 O. Bull. Geol. Soc. Am.
Vol.60, P.439-460.
Clegg, E.L.G., (1941): The Cretaceous and associated rocks of Burma: Mem. Geol. Surv.
India. V.74. part- 1.P.101
Colemen, R.G., (1977): Ophiolite Ancient Oceanic Lithosphere? Springerverleg. New Yourk.
P. 201.
Hess, H.H., (1955): A primary peridotite magma. Am.J. Sci. 35.P.321-344.
81
Hla Htay, (2006): Geology of Inkhaingbum-Myitson Area, Myitkyina township, Kachin State.
Unpublished PhD (Thesis) Yangon University.
Hutchison,C.S., (1975): Ophiolite in Southeast Asia: Bull. Geol. Soc. Am.Vol.86,
806.
P.797-
IGCP National Committee (1982): Stratigraphic Committee Field Excursion in the KawlinTigyaing-Male and Sagaing areas. Field Excursion, No.9, 58p, 2map.
Kyaw Win and Thit Wai,(1971): Geology of the Arakan-Chin ranges. Paper read at VI.
Burma Research Congress.
Maung Thein, (1983): The Geological Evolution of Burma: unpub. Report, Univ. Mdy.
Mitchell, A.H.G. et.al, (1979): Geology and Exploration Geochemistry of part of the Northern
and southern Chin Hills and Arakan Yoma, Western Burma. Technical
Report 4, UNDP, Rangon.
Miyashiro, A. (1981): Metamorphism and Convergence: Geol. Assoc. Canada Special Paper,
P.591-605.
Nyan Thin, (1991): Tectonic Environment of Jadeite deposits of Phakant-Tawmaw area,
Kachin State, Upper Myanmar. Georeports, V.1. P.49-60.
Thanyar, T.P., (1960): Some critical differences between alpine-type and stratiform
peridotite-gabbro complexes: Intern. Geol. Congr. 21st. Sess. Copenhagen.
13.P.247-359.
Wick, F.J. &Whittaker, E.J.W., (1977): Serpentine texture and serpentinization. Can-Mineral.
V.15, P.459-488.
Petrography of Igneous Rocks in Tawmore Taung Area,
Longlon Township
Su Su Hlaing
Abstract
The study area is mainly composed of the granitoid rocks which is trending
NNW-SSE. The major rock types are biotite granite (porphyry and nonporphyry) and porphyritic biotite microgranite. Minor rock types are
porphyritic two mica microgranite, hornblende biotite granodiorite, aplite,
quartzo-feldsphatic and quartz veins. Diorite and microdiorite xenoliths are
observed in the biotite granite and hornblende- biotite granodiorite. Almost
all granitoid rocks show medium to coarse-grained, hypidiomorphic
granular texture although aplite displays allotriomorphic granular texture.
Porphyritic texture, perthitic texture and myrmekitic texture are also
recognized in these rocks. Alkali feldspar, mainly perthitic orthoclase,
perthitic microcline, quartz, plagioclase and biotite are major constituent
minerals of granitoid rocks. Hornblende and muscovite occur as minor
amounts. The accessory minerals include zircon, sphene, apatite, epidote,
chlorite and magnetite. Pyrite and molybdenite specks are observed in
quartz vein and aplite dyke.
Keywords: igneous, biotite granite (porphyry and non porphyry),
porphyritic biotite microgranite, aplite, diorite and
microdiorite xenoliths
Introduction
The study area lying on the eastern flank of Maungmagan beach is
located in Longlon Township, Dawei District, Taninthayi Region. It is
bounded by latitude N14° 03' 00" to N14° 08' 15" and longitude E98° 04' 00"
to E98° 09' 00" in one inch topographic map 95J/4 and covering about 64
km2. The location map of the study area is shown in figure 1.
Assistant Lecturer, Department of Geology, University of Yangon
84
N
Figure1. Location map of the study area
Regional geologic setting
The study area lies in the southern continuation of the Shan Taninthayi
Block, Maung Thein, 1983, 2000) or Sino-Burma Range (Bender, 1983). The
study area forms a part of the Tanintharyi granite belts, which is actually a
part of Western tin-bearing batholiths called Western Tin belt of South East
Asia tin provinces (Mitchell, 1977; Thein, 1983; Nyan Thin, 1984 and
Cobbing et al, 1992). The study area is mainly composed of graintoid rocks of
Costal Range Granite, Bender (1983). The granitoid plutons intruded the
metasedimentary rocks of the Mergui Group (Carboniferous), Brown and
Heron (1923) Chhibber (1934) and Pascoe (1959). The graintoid plutons and
batholiths are markedly elongated shape with the longer axes parallel to the
NNW-SSE trend of the country rocks (Mergui Group). The granitoid rocks
form as veins, dyke, pluton and batholith. The study area is formed a part of
Certral Granitoid belt of Khin Zaw (1990). The Central granitoid belt is
developed in the tectonic setting of subduction related magmatic arc, Maung
Thein (1986). Tin- tungsten (Sn-W) mineralization is closely related and
85
spacially with granitoid rocks in this belt. The regional geologic setting of the
study area is shown in figure (2).
Figure 2. The generalized geological map of the study area (from the
Geological Map of Socialist Republic of the Union of Burma, 1977)
Purpose of study
Previous workers researched regionally on geology, mineral
occurrences, geochemistry and geochronology of the granitoids rocks of
Taninthayi, Mergui Archipelago, and Tavoy area. There is no detail research
on mineralogical, petrological and geochemical characteristics and geological
map. So, the present research mainly focuses on petrography and geological
map of the study area.
Method of study
The (65) representative rock samples were made by thin section.
Modal composition of the granitoid rocks was determined by point counting
method. The plagioclase composition of the granitoid rock was identified by
using Michell Levy’s method. The systematic classification of igneous rocks
was based on the IUGS classification (after Le Maitre, 1st edition, 2002).
Geology of the study area
The geological map of the study area is shown in Figure (3). Igneous
rocks of the study area can be divided into two groups of major rock types and
87
Rock Units
Age
Veins and dykes
Quartzofeldsphatic and quartz veins
Aplite
Porphyritic biotite microgranite
Porphyritc two mica microgranite
Biotite granite (porphyry and non- porphyry)
Paleocene to Oligocene
Granodiorite
Field study
Biotite granite (porphyry and non - porphyry) unit is the most
abundant and well exposed at Tawmore taung, Tan-daung taung, Myindawgyi
taung and also at the western flank, Maungmagan village, Kyauksin village,
Thabawseik village and Pyingyi village. Small patches of biotite granite found
in porphyritic biotite granite unit in some place. So, the contact of porphyritic
biotite granite and non- porphyritic biotite granite cannot be sharply divided at
the main range (figure 4.a). Porphyritic biotite granite is a coarse-grained
rock and the phenocrysts (about 2cm x 6cm) are exclusively alkali feldspars
which are randomly oriented. This unit is highly weathered and grain size
variation occurred in some place. Biotite granite (non porphyry) unit is well
exposed at Myawyit area. It is a coarse-grained, pale brown and reddish
brown in weathered surface and light coloured on fresh surface. Small
rounded (or) oval shape xenoliths are found in biotite granite at the seaside.
Porphyritic biotite microgranite unit is the second major unit in this
area. It occurs at the central part and the western flank of the main range.
Feldspar phenocrysts show parallel alignment at the margin (figure 4.b). There
is the sharp contact between biotite granite (porphyry and non - porphyry) unit
and porphyritic biotite microgranite unit is found at the location; North
Lattitude 14° 04' 27.1" and East Longitude 98° 06 '39.2", near Kayingyi
village (figure 4.c). Aplite dyke (at least 15 feet in width and about 400 feet
long) cut across biotite granite (figure 4.d). Molybdenite specks are observed
in aplite at Myawyit area (figure 4.e). It is trending nearly N-S, (175o – 355o).
It shows sugary texture in hand specimen and is characterized by even grainsize that rarely exceeds 2 mm in diameter. Quartzofeldsphatic and quartz
veins are found intruding into the older granitoid rocks. Pyrite specks in
quartz vein found at Myawyit area. Microdiorite and diorite xenoliths are
89
Petrography
Porphyritic biotite granite
It is a coarse-grained rock and shows porphyritic texture and
hypidiomorphic granular texture. It is mainly composed of alkali feldspar
phenocryst, quartz, plagioclase and biotite. Zircon, sphene, apatite and
magnetite are accessory minerals.
Alkali feldspars are represented by perthitic orthoclase, microcline
and microperthite. Orthoclose is euhedral in form and microcline displays
cross-hatch twining. Alkali feldspar is intergrowths with albite, and showing
perthitic texture. The size of perthitic orthoclase and microcline are between 4
mm to 6 mm in diameter. Several types of perthite such as string, patch,
flame, braid and microperthite are found. Microcline microperthite is well
developed. Euhedral plagioclase is enclosed in perthitic alkali feldspar
phenocryst (figure 5.a). It indicates that plagioclase crystallized earlier than
perthitic orthoclase. Sericitization is well developed in orthoclase. Normal
zoning is common in plagioclase. Plagioclase is euhedral to subhedral in form
and grain size varies from 1 mm to 4 mm in diameter. The composition range
of plagioclase is An 9-12 . Plagioclase is partly altered to epidote. Myrmekitic
textures are also seen in boundary of plagioclase. Quartz usually occurs as
anhedral grain. Their size varies from 2 mm to 4 mm in diameter. It shows
andulose extinction and sutured contact. The aggregrates of very small
anhedral quartz grains along the margin of large grains found as garlin form
and it is the characteristic effect of stress. Biotite is observed as subhedral
flaky form and 1 mm to 1.5 mm in diameter. It shows yellowish to dark brown
in pleochroism. Some biotite altered to chlorite along the cleavage. Zircon
occurs as inclusion in biotite and quartz. Anhedral sphene, prismatic apatite
and magnetite minerals are also observed in it. Epidote forms as intergranular
grains among the altered, untwined feldspar which showing ghost lamellar of
former plagioclase.
Biotite granite (non-porphyry)
It is a medium to coarse-grained rock and shows hypidiomorphic
granular texture and mainly composed of alkali feldspar, quartz, plagioclase
and biotite. The accessories consist of apatite, zircon, sphene, epidote, chlorite
and magnetite. Quartz occurs as anhedral large grain and size varies from 2
mm to 6 mm in diameter. It shows wavy extinction and it makes up at least 37
percents of total volume. Alkali feldspars are mostly occurred as perthitic
90
texture. Orthoclase shows simple contact twin and partly perthite. It is 3.5 mm
in width and 5 mm in length and some altered to sericite. Microcline is
subhedral form and shows crossed-hatch twin. It intergrowth with sodic
plagioclase to give perthitic texture Perthites are mainly of flame, braid and
string perthite (figure 5.b). Normal zoning plagioclases are abundant. These
are euhedral to subhedral in form and the composition of plagioclase is (An 914 ) to be albite to oligoclase. Some albites are twinned according to Carlsbad
law. Corroded plagioclase is formed by replacement of quartz. Myrmekitic
texture is characterized by the minute worm like bodies of quartz enclosed in
sodic plagioclase, usually oligoclase. It results from marginal part of potash
feldspar especially in contact with plagioclase, owing to late magmatic or post
consolidation reaction (After Williams, Turner and Guilbert, 1982).
Saussaritisation also occurred in plagioclase. Biotite is subhedral form and 0.5
mm to 2 mm in diameter. It shows light yellow, pale brown to dark brown in
pleochroism and some are altered to chlorite along the cleavage plane. Zircon
enclosed in biotite and apatite usually occurs as prismatic crystal in quartz
grains. Euhedral sphene is about 1 mm in diameter and show high relief with
the typical lozen shape.
Porphyritic biotite microgranite
It is a medium-grained rock and shows porphyritic texture and
hypidiomorphic granular texture. It is mainly composed of quartz, alkali
feldspar and plagioclase. Quartz and alkali feldspar are essential minerals.
Plagioclase and biotite are minor constituents. The accessory minerals are
sphene, zircon, apatite and magnetite. Alkali feldspar occurs as anhedral to
subhedral grains and most of them are perthitic orthoclase and microcline.
Orthoclase shows simple contact twin (figure 5.c). String perthite and
myrmekite are also found. Worm-like quartz is present along the plagioclase,
given rise the myrmekitic texture. Most of the quartz is observed as
interstitials and medium grains are also noted between 1 mm to 2.5 mm in
diameter. Corroded quartz found in alkali feldspar phenocryst. Plagioclase is
euhedral to subhedral in form and occurs as two generations (host and
inclusion). The composition of plagioclase is mainly albite (An 10-11 ). Albite
twins are very common and saussaritisation occurred in plagioclase. Biotite
mica is small in size 0.5 mm to 2 mm in diameter and flaky form. It shows
one set of perfect cleavage and some are altered to chlorite along the cleavage
plane. Euhedral zircon is found in quartz grain. Sphene is anhedral to euhedral
in form and about 0.2 mm in size.
91
Porphyritic two mica microgranite
This rock is medium-grained and shows porphyritic and
hypidiomorphic granular texture. It consists of alkali feldspar, plagioclase,
quartz, biotite and muscovite. Alkali feldspar phenocrysts are greater than 5
mm in diameter. Alkali feldspar occurs as simple twinned orthoclase (1 mm to
2.5 mm in diameter) and crosshatch twinned microcline with 0.5 to 1.5 mm
in diameter. Quartz shows wavy extinction. Some occurs as inclusions in
alkali feldspar phenocrysts. Two types of mica, biotite and muscovite are
found in this rock (figure 5.d). Biotite is altered to chlorite. Zircon is found in
biotite as inclusion. Muscovite shows one set of perfect cleavage and some
muscovites occurred as inclusion in plagioclase.
Figure 5(a) Biotite and euhedral plagioclase are enclosed in perthitic alkali
feldspar phenocryst of porphyritic biotite granite
(b) String perthite in biotite granite
(c) Simple contact twin orthoclase in porphyritic biotite microgranite
(d) Biotite and muscovite in porphyritic two mica micro granite
92
(e) Subhedral hornblende in hornblende biotite granodiorite
(f) Photomicrograph showing allotriomorphic granular texture in
aplite (All figures are between XN, 40 x)
Hornblende biotite granodiorite
It is a coarse-grained rock and shows hypidiomorphic granular texture.
It is mainly composed of plagioclase, alkali feldspar, quartz, biotite and
hornblende. It includes minor amount of epidote, apatite, zircon, chlorite and
magnetite.
Plagioclase is the most common mineral in this rock. The composition
of plagioclase ranges (An 11-17 ) albite to oligoclase. Plagioclase is mostly
euhedral in form and coarser grain than others. Their grain size varies from
1.5-2 mm in width and 3 mm-6 mm in length. Zoning plagioclases are
common and some altered to epidote. Quartz and alkali feldspar are less
abundant than plagioclase. Orthoclase shows simple twin with subhedral form
and altered to sericite. Microcline occurs as minor amount and shows crosshatch twinning. Cluster of apatite are enclosed in microcline and quartz as
inclusion. Quartz occurs as anhedral grains and 1.5 mm to 2 mm in diameter.
Biotite is more abundant than hornblende in this rock. It shows strong
pleochroism from yellowish to dark brown. Their size varies from 1 mm to 3
mm in width and 1.5 mm to 2 mm in length. Some biotite altered to chlorite.
Hornblende shows subhedral form, strong pleochroism with yellowish green
to dark green (figure 5.e). It is about 2 mm-3 mm in diameter and maximum
extinction angle is 26o. Zircon inclusions occurred in biotite and plagioclase.
Aplite
It shows fine to medium grained texture and allotriomorphic granular
texture (figure 5.f). It is mainly composed of alkali feldspar, quartz,
plagioclase and minor amount of biotite and muscovite. Magnetite and sphene
are accessories.
93
Table (1) Modal composition of the granitoid rocks in volume percent
Name
Porphyritic
biotite
microgranite
Biotite granite (Porphyry & non-porphyry)
Sample No:
Hornblende
biotite
granodiorite
3-My
C5
F.6
2.T
C1
8 MY
C9A
C9B
H1
N
14.0906
14.0962
14.1152
14.0861
14.0856
14.0856
14.0539
14.0742
14.0857
14.0563
E
98.1229
98.1307
98.1029
98.0712
98.075
98.075
98.0984
98.1083
98.071
98.0764
Location
H7
Aplite
Total count
973
983
1074
951
1015
1055
1836
1460
2049
1070
Quartz
50.56
18.69
38.73
37.01
43.84
35.82
45.47
41.23
57.75
11.08
Alkali feldspar
24.04
42.88
33.89
21.76
32.21
17.63
28.21
42.46
25.51
33.98
Plagioclase
12.53
19.2
16.10
11.56
20.29
20.18
10.13
8.49
0.73
44.54
Biotite
10.59
6.91
10.33
16.8
3.15
1.04
7.24
5.47
1.43
7.94
1.21
Hornblende
0.48
0.19
Muscovite
Zircon
0.04
Apatite
0.04
Sphene
0.20
0.19
0.10
Opaques
0.20
0.27
0.31
Epidote
0.04
0.29
0.18
25.11
2.00
12.19
0.48
12.15
Total
100.12
99.87
99.99
100
0.18
0.54
0.31
Others
99.97
0.37
99.96
8.37
99.96
2.32
99.97
12.93
0.09
0.63
0.25
99.58
99.64
94
Table (2) Modal composition of the xenoliths and host rocks in volume
percent
Name
Biotite
granite
Microdiorite
Granodiorite
Diorite
Sample No.
8 my
8 my, xenolith
C5
C 5, xenolith
N
14.1152
14.0563
E
98.1029
98.0764
Location
Total Count
951
1280
1070
1400
Quartz
37.01
9.85
11.78
8.01
Alkali feldspar
21.76
13.15
33.98
3.2
Plagioclase
11.56
55.47
44.54
63.6
Biotite
16.8
12.70
7.94
15.72
Hornblende
_
6.53
1.21
8.76
Muscovite
_
_
_
_
Sphene
0.1
0.27
_
0.39
Epidote
0.31
_
0.09
_
Opaque
0.31
1.26
0.18
1.08
Apatite
_
_
0.37
0.1
Others
12.15
1.59
_
_
Total
100
100.82
100.09
100.86
Diorite xenolith
It displays coarse-grained texture, hypidiomorphic granular texture and
consists of hornblende, plagioclase, quartz, biotite, zircon, sphene and
opaques. Plagioclase is euhedral to subhedral in form and altered to epidote
along the cleavage plane. The composition of plagioclase is An 21-25
95
(oligoclase to andesine). Hornblende is found as subhedral to euhedral grains
and maximum extinction angle about 29°. Two sets of perfect cleavage is
found in basal section. Some altered to chlorite along the cleavage plane.
Quartz usually shows undulose extinction. Euhedral sphene is observed as
wedge or spindle shape.
Microdiorite xenolith
It shows medium-grained texture and hypidiomorphic granular texture.
It consists of plagioclase, hornblende, biotite, alkali feldspar and quartz,
apatite, zircon, sphene and opaque.
7
Aplite
3
4
Biotite granite (Porphyry
and Non porphyry)
8
9
Porphyritic biotite micro
granite
5
6
Biotite bearing granite
1b =Quartz rich Granitoid
3a =Granite (syeno-granite) 1
3b =Granite (monzo-granite)
4
=Granodiorite
2
10
Hornblende biotite
granodiorite
Figure (6) Plotted data on QAP modal classification of igneous rocks (After
Le Maitre, IUGS classification, 1st edition, 2002)
96
3a = Granite (syeno-granite)
1
Biotite granite (Host rock)
4
= Granodiorite
2
Granodiorite (Host rock)
10* = Quartz Diorite
3
Diorite (Xenolith)
4
Microdiorite (Xenolith)
Figure (7) Plotted data on QAP modal classification of Host rock and
Xenoliths (After Le Maitre, IUGS classification, 1st edition, 2002)
Summary and conclusion
The study area is mainly composed of the granitoid rocks which is
trending NNW-SSE. The major rock types are biotite granite (porphyry and
non-porphyry) and porphyritic biotite microgranite. Minor rock types are
porphyritic two mica microgranite, hornblende biotite granodiorite, aplite,
quartzofeldsphatic and quartz vein. Diorite and microdiorite xenoliths are
observed within the biotite granite and hornblende biotite granodiorite.
The petrographic characteristics of granitoid rocks show medium to
coarse-grained texture, hypidiomorphic granular texture although aplite
displays allotriomorphic granular texture. Porphyritic texture, perthitic texture
and myrmekitic texture are also recognized in these rocks. Biotite is very
common minerals in these rocks. The plagioclase composition of biotite
granite (porphyry & non-porphyry) and porphyritic biotite microgranite is
albite (An 9-12 ), where as its composition range from albite to oligoclase (An 1117 ) in hornblende biotite granodiorite. Potash feldspar megacrysts and
phenocrysts are mostly abundant in biotite granite (porphyry and non-
97
porphyry) unit, showing perthitic texture which indicates feldspar formed at
high temperature that have cooled slowly, result in unmixing as the solvus
curve. Small patches of biotite granite found in porphyritic biotite granite unit
due to variation of viscosity and cooling temperature of magma.
Acknowledgements
This paper is part of my PhD research and I respectfully thanks to my supervisor,
Professor U Hla Kyi who patiently guided my research work and discussion.
My greatful thank want to Dr. Day Wa Aung, Professor and Head of the Geology
Department, Yangon University for his permission and valuable administrative supports.
I also wish to express my appreciation to U Aung Kyaw Htun, formerly Lecturer of
Geology Department of Mawlamyine University for his participation and suggestions in the
field of the present investigation.
References
Augustithis, S.S., (1973). Atlas of the textural patterns of Granites, Gneisses and Associated
Rock Types. Amsterdam, Elservier, Sci. Pub.
Barth,T. F.W., (1969). Feldspar. New York, Wiley, 216 p.
Bender, F., (1983). Geology of Burma. Gebrder Borntager, Berlin. 293 p.
Cobbing, E. J., Pitfield, P. E. J., Darbyshire, D. P. F., and Mallick, D. I. J., (1992). The
granites of the South-East Asian tin belt: Overseas Memoir 10, British
Geological Survey, 369p.
Darbyshire, D.P.F & I. G. Swimbank, (1988), Geochronology of a selection of ganites from
Burma, South-East Asia granite Project.
Khin Zaw, (1990), Geological, Petrological and geochemical characteristics of granitiod rock
in Burma with special reference to the associated W-Sn mineralization and
their tectonic setting. Journal of Southeast Asia Earth Sciences, Vol. 4, No.
4 pp. 293-335.
Le Maitre, (2002), IUGS classification of igneous rocks. 1st edition,)
Maung Thein, (1983), the Geological Evolution of Burma, Department of Geology, Mandalay
University, Burma, Unpublished
Maung Thein, (2000), Summary of the Geological history of Myanmar, Department of
Geology, Yangon University.
Mitchell, A.H.G, (1977), Tectonic setting for emplacement of Southeast Asian tin granites:
Journal of the Geological Society of Malaysia, Vol. 9.
Nyan Thin, (1984), Some Aspects of Granitic rocks of Tenasserim Division, Univ. of
Rangoon.
Williams, Turner and Guilbert, (1982). Petrography.
Geology and Mitigation of Landslide Hazard along SittwayMrauk Oo Car Road, Rakhine State
Than Than Oo
Abstract
The study area lies in the western Ranges and Arakan Coastal Plain. These
provinces are inherently unstable area because they have steep slopes,
unstable geology and intense monsoon rains. The Arakan Coastal Zone is
comprised of tightly folded sandstone and siltstones of dominantly Miocene
age. The Northern Arakan Coastal Area is predominantly covered by thick
sequence of Miocene sediments. The sediments deposited in the northern
Arakan Area can be subdivided into four main groups as follows;Recent
Sediments,Pliocene Rocks ,Miocene Rocks and Undifferentiated Eocene –
Miocene Sediments. According to the clay content map and the iron
content map of the study area, the higher the clay content, the lower the iron
content in this study area. In the study area, land cover map reflects forest,
bamboo, and grass land. The main factors that influence slope stability are
Gravity and slope gradient, Hydrologic characteristic, the process of erosion
and Man-made causes. Along Sittway- Ann car road, the most common
types of land slide are slump, flow and slide. For prevention the landslide,
the excavation methods are designed to increase the stability of landslide.
The chief methods are (a) Removal of head (b) Flattening of slopes (c)
Benching of slopes (d) Complete removal of all unstable
materials..Drainage management has significantly improved slope stability
of landslide. Structural support measures improve the stability of slope by
increasing stabilizing component of sliding mass. Structure support
measures include retaining wall, anchored structures, rockbolts, earth
anchors and rock anchor.Bio-engineering is the use of living vegetation to
reduce shallow seated instability and erosion on slopes.
Introduction
Myanmar has experienced many types of geologic hazards including
earthquakes, landslides and subsidence in karst area. Among these, landslide
is major hazard affecting the country. Geomorphologically, Myanmar has two
mountainous provinces namely the Western Ranges and the Eastern Highland.
Sittway-Ann car road pass through in the Western Ranges. Fig (1) This
provinces is inherently unstable region because of steep slopes, unstable
geologic condition and heavy monsoon rains. These features make the
landslide hazards in these regions. The present research supports to landslide
investigations along Sittway-Mrauk Oo car road by using the field
Dr, Professor, Department of Geology, Dagon University
100
investigations,
investigations.
Remote-sensing
techniques,
and
other
geological
Fig 1. Location map of the study area
Materials and Methods
The research work was conducted using the following instruments;
One inch topographic map references, Aerial Photographs, Landsat TM
images, Brunton Compass, Hammer, GPS, Stereoscope, Tape, Digital camera,
and Computer.
Field methods
Tape and Compass Traverse method was applied in the field. The data
measured was plotted in the field on eight inch scale field sheet and converted
to one inch scale geological maps. Representative samples were collected by
using the GPS and hammer. Record details of locations and lithology in the
field notes and took the photos. Slope and other geological structures were
measured by Brunton Compass
.
101
Laboratory Methods
Literature survey was carried out by reading so many references books
at the library and by downloading web site from the internet. Remote sensing
techniques and GIS techniques were also applied by using Landsat TM
images with the aid of computer software such as Arc Gis 9.1, EDRAS
Imagine 8.6, Arc Map 3.2.
Representative petrographic thin sections were made from different
lithologic units. Petrographic study was made by using transmitted light
microscopy.
Regional Geologic Setting
Geomorphologically as well as tectonically, Myanmar has been
divided into four major tectonic units, from west to east, namely Arakan
Coastal Plain, the Western Ranges, the Central Lowlands and the Eastern
Highlands. Geologically, Myanmar has two mountainous provinces namely
the weastern Ranges and the Eastern Highland. The study area lies in the
western Ranges and Arakan Coastal Plain. These provinces are inherently
unstable area because they have steep slopes, unstable geology and intense
monsoon rains.
The Arakan Coastal Belt represents the Indonesian-Andaman
foredeep, marking the subduction zone. The Arakan Coastal Zone is
comprised of tightly folded sandstone and siltstones of dominantly Miocene
age. (Fig 2) The folded and faulted molasses sediments of late Tertiary age is
overlying Early Tertiary flysch rocks, locally intruded by basaltic to
intermediate dykes and plugs.
General Geology
The Northern Arakan Coastal Area is predominantly covered by thick
sequence of Miocene sediments. Band combination of 732 RGB map of the
Arakan Area is shown in Fig (9). The general trend of the strike is
NNW_SSE.
Stratigraphy
The sediments deposited in the northern Arakan Area can be
subdivided into four main groups according to Kyaw Win, Thit Wai & Khin
Maung Lwin (1970) as follows;
(a) Recent Sediments
102
(b) Pliocene Rocks
(c) Miocene Rocks
(d) Undifferentiated Eocene – Miocene Sediments.
Fig. 2. Regional geologic Setting of the study area
(d)Undifferentiated Eocene – Miocene Sediments
These sediments are found in the western foot hills of Arakan Yoma to
the east of the Arakan fault. They are mostly indurate shale and clay, hard,
well stratified, occasionally interbedded with very hard thin greywackes. The
103
thickness of the formation is estimated between 8000 ft and 12000 ft.
According to the paleontological results, parts of the sediments contain fauna
indicating Miocene age. Due to infolding of later Miocene sediments, this
may be in the Eocene.
(c) Miocene Rocks
The rock group exposed in the study area can be subdivided into the
following formations.
Table (A) Stratigraphic units of the Miocene Rocks. ( Kyaw Win, Thit Wai &
Khin Maung Lwin) (1970)
Stratigraphic units
6. Kyauktan Formation
Age
Pliocene
5. Ngasanbaw Formation
4. Mayu Formation
3. Yezaw Formation
Miocene
2. Laung Formation
1. Undifferentiated Yezaw/ Laung Formation
1. Undifferentiated Yezaw/ Laung Formation
To the east of the Myohaung, Minbya and Myebon areas, the
undifferentiated sediments of Yezaw and Laung Formation are exposed. The
name has been applied to the large shale sequence underlying the Mayu
Formation. The dominant lithologies are shales, clays siltstone and rarely
sandstone. Shales are blackish grey to grey, hard, fissile carbonaceous,
micaceous and silty. Clays are grey, hard with nodular structure. Siltstones are
associated with shale and clay beds. The sandstones are very fine to finegrained, grey to brown, very hard and micaceous.
2. Laung Formation
The type area of the Laung Formation is in the Ponnagyun. The
sequence is predominantly composed of shale and clay with occasionally
interbedded thin sandstone beds varying from 6 inch to 5 feet. Fig (3) In some
places, individual sandstone bodies were found to have less than 50 feet in
thickness. The weathered colour of shales is brown and the fresh colour is
104
dark grey to grey. The shales are hard, thinly bedded, micaceous. Clays are
chracterised by nodular structure. Sandstone are brown to grey, hard to very
hard, fine to medium grained, thinly bedded micaceous with ripple marks. The
maximum thickness obtained in Madema- Yotarok section is 6680 feet.
3. Yezaw Formation
This formation is widely distributed in the crested parts of Mayu
Anticline, Uga Anticline, Seshatauing Anticline, Taung yiyo Anticline,
Romadaung Anticline, and Tawbya Syncline. The upper and lower portions
are predominantly composed of sandy shales and clays. In some places, they
are interbedded with thin sand beds which are 6 inch to 3 feet in thickness.
Sandstones are grey to brown, hard, fine to medium grained and micaceous.
Sedimentary structures such as current bedded and ripple marks are also
observed. The shales are dark bluish grey with thin laminations of sand. Clays
are dark grey and nodular. Fig (4)The measure thickness is over 6000 feet.
Fig 3. Outcrop nature of the Laung Formation
105
Fig 4. Outcrop nature of the Yezaw Formation
4. Mayu Formation
Most of the prominent ridges are formed by this formation. It is widely
distributed in the northern part of the Arakan Coastal Area. It is mainly made
up of sandstone, occasionally interbedded with shale and clay. Fig (5) The
upper parts of sandstones are brown, medium to coarse-grained, micaceous
and calcareous, rarely interbedded with shale partings. The lower parts of
sandstones are grey, hard, and fine to medium grained with shale laminations.
Ripple marks and current bedding are fairly common. Shales are dark grey to
grey with sand stringers. The maximum thickness is 5800 feet.
5. Ngasanbaw Formation
This formation is unconformably overlain by Kyauktan Formation and
underlain by Mayu Formation. It is mainly made up of shale, clay and fairly
sandstone. Shales are grey to dark grey fairly hard, and sandy.Fig (6) The
maximum thickness is 4000 feet.
107
of sandstones are buff, coarse-grained, loose by consolidated micaceous and
ferruginous, in places very silty. The maximum thickness is about 7000 feet.
Fig 7. Outcrop nature of Kyauktan Formation
Geological Structure
Folds
The major structure of the Ponnagyun Area is Ponnagyun monocline.
This structure is formed between Tawbya River and Yo River. The dips of the
structure are between 30˚-60˚ degree on the west, steeper dips range 55˚-65˚
degree to the east in the intermediate vicinity of Ponagyun fault. The structure
is entirely dominated by shale /clay and thin sandstone of Laung Formation.
Minbya Anticline was first identified south of Minbya and extends up
to the Myebon Area. It is highly composed and tight fold trending NNW-SSE.
The general dips of western flank are 40˚-55˚ degree and more gentle dip was
observed on the eastern flank. This structure is highly affected by
longitudinalfaults.
Melun Anticline was found in Kyaukkok-Sinoh and WetgaungZinyawmaw – Kangaw chaung traverses. The structure is broad, wide and less
disturb. It was found to be highly compressed and tightly folded especially in
the crestal part. The average dips of the west flank are between 65˚-70˚ degree
and those on the eastern flank are between 45˚-55˚ degrees.
108
Faults
Two large faults are encountered in this area. Myohaung thrust fault
can be traced from the north of Paletwa through Myohaung up to the Myebon
Area for a distance of over sixty miles. The fault is trending NNW-SSE.
Arakan fault (Hpontha fault) is a major thrust fault, situated near
Hpontha village which separates the Miocene sediments from those of Arakan
Yoma. It extends to the north of Pyelongyi and southwards, it can be traced up
to Gwa area, across the Arakan Yoma. It covers a total distance of over two
hundard mile along the western foothills of the Arakan Yoma.
The eastern limb of Ponagyun Monocline is cut off by the Ponnagyun
fault. A series of regional strike and cross faults are also encountered.
Landsat TM Image Interpretation by Remote-sensing Techniques
Radiometric interpretation of multispectral features is mainly applied
to rock type classification. Colour composite of bands 4, 5, and 3 of landsat
TM and bands 7, 3, and 2 of landsat TM are illustrated in Fig (8) and Fig (9).
They are applied to classify rock types of the study area. The clay content map
of the study area is illustrated in Fig (10) and the iron content map of the study
area is also illustrated in Fig (11). The higher the clay content, the lower the
iron content in this study area.
Land cover mapping is one of the most important and typical
application of remote sensing data. Land cover corresponds to the physical
condition of the ground surface for example forest, grassland. Land cover map
of the study area is illustrated in Fig (12). In the study area, land cover map
reflects forest, bamboo, and grass land. NDVI (normalized difference
vegetation index) map of the study area is also illustrated in Fig (13).
112
Landslide Hazard of the Study Area
Definition of Lanslide
Landslides are the most common geological hazards in the world. The
term landslide is commonly used to denote the downward and outward
movement of slope-forming materials along surface of separation by falling,
sliding, and flowing at a faster rate.Fig (14)
Goodman,1985
Fig 14. The classification of landslide. (Goodman,1985)
Causes of Lanslide
Many factors affected slope stability. A change in any one or a
combination of these factors can alter the steady and sometimes leading to
slope failure.
The main factors that influence slope stability are
(1) Gravity and slope gradient
(2) Hydrologic characteristic
(3) The process of erosion
(4) Man-made causes
(1)
Gravity and slope gradient
Shear stress and shear strength determine whether a body of rock
debris located on a slope will move or remain stationary. Shear stress may
113
cause movement of the body parallel to the slope. As a slope become steeper,
the shear stress become larger. Fig (15) DEM of the study area is shown in Fig
(16) Shear strength exceeds shear stress, the rock or debris will not move.
F= Shear strength/ shear stress,
F= safety factor<1, slope failure is imminent
Dip of the bedding planes are nearly the same as these of the slope
causing planar sliding.
Stable slope along Sittway-Ann car
roa
Slope is 45 ̊ along Sittway-Ann Car
road
Slope is 60˚ along Sittway-Ann Car road
Fig 15. The slope nature of the study area
114
Fig (16) DEM of the study area
(2) Hydrologic characteristic
Rhakhine Coastal Area is heavily rainfall in the monsoon. Fig (17 &
18 ) Annual rainfall data of the Sittway, Ponnagyaung, Kyauktaw, Mrauk_Oo,
and Ann are illustrated in the Table (C). Groundwater rises up in the
monsoon. Because of the rising of ground water table, it causes the saturation
of the soil. It destroys the capillary tension in soil and reduces its cohesion
because of increasing moisture content.
Fig 17. Rain fall data along Sittway –Ann car road, 2010
115
Fig 18. Rain fall data along Sittway – Ann Car Road, 2009
Table (B) Annual rainfall data of the Sittway, Ponnagyaung, Kyauktaw,
Mrauk_Oo and Ann
Town
Year
Jan
Feb
Mar
Apr
May
June
July
Aug
Sept
Oct
Nov
Dec
Sittway
2009
-
-
-
1.02
5.84
29.99
72.82
24.33
21.2
12.53
-
-
2010
-
-
-
-
27.62
37.52
44.74
27.64
15,66
11.26
0.55
4.26
Ponna
2009
-
-
-
2.36
7.18
31.49
81.9
30.86
26.31
9.72
0.14
-
gyaung
2010
-
-
0.94
0.08
26.1
38.01
48.63
24.0
18.96
22.53
0.1
8.57
Kyaukta
w
2009
-
-
-
4.77
12.47
21.32
58.54
23.72
17.15
7.83
0.40
-
2010
-
-
3.31
3.38
24.96
41.15
29.83
19.59
15.01
16.09
0.87
Mrauk
Oo
2009
-
-
-
3.85
11.19
24.15
54.78
22.02
15.31
6.27
-
-
2010
-
-
1.5
3.74
16.65
38.8
27.97
12.16
12.91
21.68
0.12
4.61
Ann
2009
-
-
-
3.35
3.72
30.16
52.53
24.61
20.39
2.99
-
-
2010
-
-
-
1.18
16.97
23.64
19.61
29.45
15.20
18.95
-
1.42
(3) Process of erosion
During the raining season, high flow velocity of rain water on the
slope surface washes out soil and boulder that will destroy road.
116
(4)Man-made causes
Man-made land slide are due to large-scale deforestation, blasing and
quarrying.
Types of Landslide Hazard along Sittway – Mrauk Oo Car Road
Along Sittway- Mrauk Oo car road, the most common types of land
slide are slump, flow and slide.
A slump is a type of slope failure involving rotational movement of
regolith, that is downward and outward movement along a curved, concave-up
surface (Fig 19). They are common along car road where bordering slopes
have been over steepened by construction activity.
When a sufficiently large force is applied, any deformable material
will begin to flow. The movement of such mixture is called flows. Debris flow
involves the down slope movement of regolith whose consistency is coarser
than that of sand (Fig 20).
Slide involves rapid displacement of mass of rock or sediments.It is
uniform movement in one direction with no movement. They involve the
movement of relatively coherent blocks of materials along well-define planes.
(Fig 21) Slide are common in high mountain where steep slope abound.
Fig 19. Slope failure give rise to slump along Sittway-Ann car road.
117
Fig 20. Debris flow occur on the mountain side.
Fig (21) Slide involve the movement of relatively coherent blocks of materials
along well-define planes.
Prevention
The excavation methods are designed to increase the stability of
landslide. The chief methods are (a) Removal of head (b) Flattening of slopes
(c) Benching of slopes (d) Complete removal of all unstable materials. The
slope ratio of the road-cuts should be 1.5:1.
Some of the landslides were associated with drainage problem.
Drainage management has significantly improved slope stability of landslide.
118
Structural support measures improve the stability of slope by
increasing stabilizing component of sliding mass. Structure support measures
include retaining wall, anchored structures, rockbolts, earth anchors and rock
anchor.
Bio-engineering is the use of living vegetation to reduce shallow
seated instability and erosion on slopes.
References
Aung Khin & Kyaw Win (1969) Geology and Hydrocarbon Prospect of the Burma Tertiary
Geosynclines, Burma Oil and Gas, Union of Burma. Jour. Sci &
Technology Vol. 1.
Bender, F.,(1983) Geology of Burma. Gebruder, Borntraeger Berlin-Stuttgart.
Chhibber, H.L., (1934) The Geology of Burma. Macmillian and Co., London.
Keller, S.P. (1988) Environmental Geology. Fifth Edition Merrill Publishing Company.p 121142
Kyaw Win, Thit Wai & Khin Maung Lwin (1970) Geological Report on Northern Arakan
Coastal Area, Unpublished Report, MOGE.
Plummer Charles, et al.,(1993) Physical Geology. Sixth edition,Wm. C Broum
Communications,Inc.,p 182-188.
A Study on Mineralogy of Gold Ores from Myanmar Deposits
Moe Min Soe
Abstract
In Myanmar gold deposits occur from Putao in the extreme north to
Kawthaung in the extreme south. They are found in a great diversity of
geological environments resulting in diverse mineral assemblages and goldbearing minerals. Native gold is the common form found in nature. The
next most common is electrum, an alloy of gold and silver, which have
been identified in the gold- silver epithermal deposits at Kyaukmyet and
Shwebontha of the Monywa district. Copper-gold systems have been
reported from Shanganlon, Kawlin, Patun, Banmauk and from skarn
deposits of Shweminbon, Kalaw. Gold tellurides occur in the Kyaukpazat
Mine, Wuntho. Free-milling gold ores are those that can be readily
recovered by gravity separation and / or amalgamation. In Mandalay region
the Phayaung Taung ores are Free-milling. Most of the Myanmar deposits,
gold occurs as fine particles disseminated and locked in sulphide grains
such as pyrite and arsenopyrite. They are known as refractory gold ores
which can cause low recovery in processing even when cyanidation is used.
Gold ores from Kyaukpatho are highly refractory. In gold mining, the
mineralogy of the gold ores greatly influence the proper choice of
metallurgical process route for treatment.
Key words: Electrum, Gold tellurides, Free-milling gold, Refractory gold.
Introduction
This research paper focuses on the mineralogy of gold ores from
Myanmar deposits. In Myanmar gold deposits occur from Putao in the
extreme north to Kawthaung in the extreme south. Gold deposits are found in
a great diversity of geological environments resulting in diverse mineral
assemblages and gold-bearing minerals. Gold occurs in a variety of rock types
in different geological ages, in the Chaung Magyi turbidities of Precambrian
terrains to sub-aerial volcanics of the Popa region.
Purpose of Investigation
To understanding the mineralogy of the gold ores, the mineral
assemblages, fineness and their refractoriness will help in the proper choice of
metallurgical processes for treating the diversed typed of gold ores found in
Myanmar. This can be a valuable aid to increase recoveries and eventually
increasing revenues.
Dr, Lecturer, Department of Geology, West Yangon University
120
Methods of Investigation
Investigation involves literature review, field observation on features,
as rock types, strucutres,alteration and mineralization laboratory work
involves ore microscopy and other advanced analytical techniques X-rays,
chemical analysis is commonly by AAS- (Atomic Absorption
Spectrophotometer) The current study is not focused on a single orebody,
deposit or district but on the entire
region within the Litho - tectonic framework.
Geological Settings of Gold
Economic gold deposites of Myanmar occur in four major metallogenic
provinces. They are: the Inner Volcanic Arc (IVA)of the Wuntho massif, the
Back Arc Basin (BAB), the Mogok Metamorphic Belt (MMB) and the Slate Belt (SB).
•
The Inner Volcanic Arc is the northern continuation of the Sunda Arc of
Sumatra, Indonesia and the major gold metallogenic province is on the
Wuntho massif. Andesitic rock, volcanolastic sediments and I-type
granitoids are the principal rock types. Gold mineralization is related to
the high-level intrusions of diorite and dacite plutons.
The types of gold deposits include; copper-gold systems (Shangalon,
Lemi), quartz- pyrite, arsenopyrite- gold (Muthein, Hechein) goldtellurides (Kyaukpazat), high-sulphidation deposits (Patun, Khamauk
taung) low-sulphidation epithermal Au-Ag deposits at (Kyaukmyet,
Monywa district) and gold deposits associated with sub-aerial
volcanism. (Popa region). This results in the diversity of mineral
assemblages.
•
The Back Arc Basin-It lies immediately to the east of IVA and to the
east , it is bordered by the Sagaing wrench fault. Gold mineralization is
hosted in sediments; calcareous sandstones and argillaceous limestones
of Cretaceous to early Tertiary age. These deposits are thought to be of
Carlin affinity. The mineralogic assemblage is dominantly iron
sulphides-gold. At Kyaukpahto gold is micron-sized, encapsulated in
arsenian pyrite, an overgrowth of pyrite grains. jThe gold are is
notoriously refractory causing low recoveries even by cyanidation. The
mineralization in limestones is characterized by the widespread presence
of jasperoids indicating intense silicification. The jasperoids are
typically anomalous in gold. (Gegalaw, Sheinmaga).
121
•
The Mogok Metamorpic Belt-Within this belt gold mineralization is
hosted by metamorphic rocks, gneisses and marbles in the Thabeikkyin
goldfield and is probably related to the late intrusives. The mineral
deposite types rang from mesothermal copper-gold systems
(Chaunggyi). The base metals-gold (Kantaung) to epithermal gold-silver
deposite (Doe Nwe). Along the MMB gold mineralization in
metamorphics is also found in the Pyinmana goldfield and a intrusion related gold deposite along the Sittoung Valley. (Mobaw, Meyon).
•
The Slate Belt -This belt borders the MMB to the east extending along
the Shan Scarp. The host rocks are epimetasediments; quartizites and
phyllites of the Chaung Magyi Group (Precambrian) in the north at
Phayaung Taung and, pebbly mudstones (Upper Carboniferous) at Modi
Taung, the gold ores are dominantly free-milling.
Source : A H G M ITCHELL et al, 1999
Fig : (1) Map of northern and central Myanmar showing major structural
belts.
122
Mineralogy of Gold Ores
Although gold is inert it is found to occur in a number of gold-bearing
minerals (Table 1) Native gold (natural alloys of gold with other metals,
particularly Ag) occurs in a variety of forms in different deposits. In primary
deposits as a whole the native gold can range in size from less than a micro to
several centimeters. In place deposits gold nuggets up to 15cm have been
found. (Soe Win, 1994) The shape is also variable, plate- like, rounded wirelike and irregular. Besides native gold, the most important and commonest of
the gold-bearing minrerals ore those that have the composition (Au, Ag, Cu)
where Au is greater than 50 percent. These have been identified in the goldsilver epithermal deposit at Kyaukmyet and Shwebontha of the Monywa
district. Copper-gold system at Shangalon, Kawlin (Ohn Thwin, 2004) and at
Lemi, Banmauk (Zaw Linn Aung,2011) The second group of elements
forming metallic compounds with gold are the platinum group metals (P G
M). These metals have melting points higher than that of gold. These
minerals could probably be found in the Indawgyi Lake and the Jade mines
area. The third group forming metallic compounds and complexes with gold
belong to the element of Hg, Pb, Sb, Bi, S, Se and Te. Gold tellurides occur
in the Kyaukpazat mine, Wuntho (Cho Cho Aye, 2006) Gold is associated
with the antimony ores at Lebyin (Mitcheel etal, 1999). Antimonides of gold
ores are rare. To the above three types of gold-bearing minerals, a fourth class
must be added "invisible gold" that form in solid solution or submicron
inclusions in sulphide minerals and sulphosalts.
Table 1 Some gold bearing minerals
Mineral
Formula
%Wt Au
Native gold
(Au,Ag)
>80
Electrum
(Au,Ag)
50-80
Cuproauride
(Au,Cu)
not available
Cuprian electrum
(Au,Ag,Cu)
not available
Porpezite
(Au,Pd)
90-95
Iridic gold
(Au,Ir)
not available
Platinum gold
(Au,Pt)
not available
Gold amalgam
(Au,Hg)
34.3-41.6
123
Mineral
Formula
%Wt Au
Aurostibite
(AuSb2)
43.5-50.9
Calaverite
(AuTe2)
39.2-42.8
Sylvanite
(Au,Ag)Te4
24.5-29.9
Petzite
(Ag3AuTe2)
19.0-25.2
Hessite
(Ag2Te)
<4.7
Uytenbogaardtite
(Ag3AuS2)
not available
The following are extraction-oriented classification of gold ores.Native gold precious metals that can be removed by gravity separation, amalgamation and/
or cyanidation. Gold associated with sulphides - gold occuring either as free
particles disseminated in sulphideauriferous pyrite. Gold telluridesCalaverite, krennerite occur along with native gold and other Sulphides.
These minerals contain 40% gold. Gold in other minerals - aurostibite AuSb2
with Pb , Zn minerals and with carbonaceous materials.
Simple (non refractory ) and refractory gold ores
Fig : (2) Photomicrograph showing
native gold liberated or locked
in pyrite and quartz Kyaukpahto
gold mine. Courtesy Dr. Cho
Cho Aye
Fig : (3) Photomicrograph
showing
native larger gold grain locked
hematite. Courtesy Dr. Cho Cho
Aye
124
Fig : (4) Polished section showing buck Fig : (5) Polished section showing free
quartz, breccia infill with
gold in quartz (Phayaung
Taung)
hematite matrix, fracture filling
of
hematite
and
gold
( Phayaung Taung )
Fig : (6) Native gold (bright yellow)
associate with hematite (light
grey) Thanatkha myaung
(Thayet-pin-gaing area)
(Polished section)
Fig : (7) Disseminated
gold
grains
(bright yellow) and sphalerite
(dark grey) Dawwa-gyaung
area (Polished section under
reflected light)
Simple gold ores are those which are readily amenable to direct cyanidation
producing gold recovery in excess of 90 percent. Refractory gold ores are
difficult to treat and on cyanidation recover less than 90 percent Au
(Yamopoulos, 1991) However, degrees of refractoriness of gold ores ranging
from weakly to strongly refractory. Cyanidation of strongly refractory gold
ores may extract less than 30-50% Au even after fine grinding. The major
causes of refractoriness of gold ores may be due to one or a combination of
125
the following: The gold minerals themselves are insoluable in cycanidetellurides. The presence of cyanicides which are ingredients of the ore that
might decompose and react with cyanide. The physical nautre of the gold ores
are the main cause of refractoriness. This can be specified by microscopic
mineralogy. Gold encapsulated in pyrite, arsenopyrite, silica or attached to
carbon. The Kyaukpahto gold ores encapsulated in arsenian pyrite grains (Ye
Myint Swe, 2004 ). Most of the primary gold ores in Myanmar are refractory
ores (Thabeikkyin, Wuntho massif) warranting cyanidation
for gold
extraction (Soe Win, 2011). Free -milling, non- refractory gold ores are found
at Phayaung Taung. (Moe Min Soe, 2009) and partly refractory ores occur in
the Modi Taung area. The simplest way of pre-treating refractory ores is
roasting.
Fig : (8) Micron sized gold particles Fig : (9)
encapsulated in chalcopyrite
(Polished section) (Sample
No.PTR-43, Lemi prospect)
Courtesy Dr. Zaw Linn Aung
Gold specks in fractures of
arsenopyrite (Sample No. PTR43, Lemi prospect) (Polished
section) Courtesy Dr. Zaw Linn
Aung
126
Fig:(10) Photomicrographs showing
small gold particles
encapsulated in the matrix of
pyrite (Kyaukpazat) Courtesy
Dr. Cho Cho Aye
Fig:(11) Photomicrographs showing
native gold locked in galena
along grain boundary and
along the micro-fractures in
pyrite (Kyaukpazat)Courtesy
Dr. Cho Cho Aye
Fineness of Gold
The fineness of gold is defined as {Au / ( Au + Ag)} x 1000 and varies
considerably for native gold. The fineress of 900 means 90% of gold. The
fineness of native gold ranges from about 450 to 900 + and the fineness of
gold from different geological environments is shown in Table (2).
Table (2) Fineness of gold from different geological environments
Source
Mean fineness
Ranges of fineness
Archaean
940
780 - 1000
Slate-Belt
920
800 - 1000
Plutonic
Porphyry
825
700 - 1000
650 - 970
650 - 1000
Volcanogenic
650 - 850
520 - 870
Hypothermal
925
not available
Mesothermal
900
not available
Epithermal
440-1000
0-1000
127
These are many causes for the variation of fineness
•
Pressure - temperature - depth of gold formation in igneous rocks and
the geoloical age of rocks attributed to the fineness ( Campbell, 1997).
•
Other worker believe that the finenes of gold is determined by such
factors as paragenesis composition of the mineralizing fluids mode of
formation, metamophism and post-crystallization events ( Morrison
etal, 1991) Corbett and Leach ( 1995) have shown that there is a
sysematic decrease and shallower levels or distal from the intrusive
source.
•
Porphyry copper / skarn systems (average: 920)
•
Quartz - sulphide (average : 765)
•
Epithermal quartz - silver - gold systems (average : 685)
They attributed the zonation of fineness to temperature as the most
important control. For the copper-gold system at Shangalon Kawlin the gold
fineness was stated as 800. (Ohn Thwin, 2004). For the gold ores from
Phayaung Taung, the gold fineness ranged from 850-920. ( Moe Min Soe,
2009). The variable fineness is apparaently related to the gold mineral
assemblages. Both temperature and distance from the source are the probable
causes. It is important that in stating the gold fineness to clearly differentiate
whether the assays were from the gold ores or that from the gold-bearing
minerals.
Conclusion
The geologic settings for gold mineralization in Myanmar occur in four
major metallogenic provinces. Gold occurs in a variety of rock types of
different geological age. The mineralogy and the refractoriness of the gold
ores greatly influence the proper choice of metallurgical processes for treating
the various gold ores found in Myanmar.
Acknowledgements
I whish to express my sincerely gratiude to Dr. Myo Thant, Professor and Head of
the Department of Geology, West Yangon University for allowing me to undertake this
research paper.Profound gratiude and respect is due to U Soe Win ,Consultant,Geological
Engineer,who initiated me in the field of economic geology and superbly supervised my
research work.Finally I gratefully thank many researchers on gold deposits.
128
References
Antwiler J.C, and Campbell W.L (1977),Application of gold compositional analysis
mineral exploration in the United States.Journal of Geochemical
Exploration.
Cho Cho Aye (2006) Mineralogical investigation of gold ores from Kyaukpazat,Kyaukpahto
and Phayaung Taung mines and their process implications.PhD
dissertation.University of Yangon.Unpublished.
Corbett,C.J and Leach T.M (1995) SW Pacific gold-copper systems,Structure,alteration and
mineralization.Workshop Pacrim Conference,Auckland,NewZealand 22-23
Nov.1995.
Mitchell,A.H.G,Nyunt Htay,Ausa.C,Deiparine,Aung Khine and Sein Po(1999) Geologic
setting of gold districts in Myanmar.99,Bali Indonesia.
Moe Min Soe (2009) Geology and geochemistry of the Phayaung Taung gold mineralization
extension area, Mandalay Division PhD dissertation.University of
Yangon.Unpublished.
Morrison,E.W,Rose,W.J and Jurieth,S(1991)Geological and geochemical (fineness)of gold
in gold-silver deposits.Ore Geology Review 6:333-364.
Ohn Thwin (2004) Systematic investigation of copper-gold mineralization at Shangalon
area,Kawlin
Township,Sagaing, Division,Upper Myanmar.PhD dissertation University of Yangon.
Unpublished.
Soe Win (2011) Small scale mining in Myanmar.Paper read at the Seventh Annual
Conference Myanmar Engineering Society.Yangon.
Yannopoulos,J.C(1991) The Extractive Metallurgy of Gold.Van Nostrand Reinhold,New
York.
Ye Myint Swe (2004) Geology,Mineralization and wall rock alteration at Kyaukpahto gold
mine.Northern Myanmar PhD dissertation.University of Yangon.
Unpublished.
Zaw Linn Aung (2011) Controls on gold-copper mineralization at Patun area,Banmauk
Township, Sagaing Division,PhD dissertation.Universisty of Yangon
Unpublished.
Microfacies Analysis of the Linwe Formation in the area,
northern part of Bawsaing Range, Shan State (South)
Aye Aye Han
Abstract
Microfacies analysis of the Linwe Formation exposed in the area, northern
part of Bawsaing range, Shan State south was carried out. Based on the
particle component, texture and sedimentary structure, six microfacies such
as lime mudstone, bioclastic lime mudstone, biointraclastic wackestone,
bioclastic wackestone, bioclastic lithoclastic packstone and bioclastic
packstone are recognized. These microfacies fall into four main depositional
environments, namely, basin, open sea shelf, deep shelfmargin and fore
slope by identifying their grain type, physical, biologic and sedimentary
structure.
Key words: Microfacies, Linwe Formation, Bawsaing Range
Introduction
Linwe Formation is well exposed and widely distributed in the area
northern part of Bawsaing Range. The investigated area is bounded by latitude
21° 03' N to 21° 07' N and longitude between 96° 45' E and 96° 55' E
(Figure.1). Thin sections cut from representative specimen are used for
petrological studies. Petrographic classification used in the present research
are adopted from Dunham (1962), Folk (1965) and Pettijohn 1956.
Microscopic descriptions are followed by Horowitz and Potter (1971) and
Adam and Mackenzie (1998).
Methodology
Firstly literature survey, then field investigation and geological
mapping were carried out. Samples collection and taking photographs if it was
necessary were performed during field investigation. After that, cutting thin
sections from representative specimens and petrological studies by means of
microscopic examination are done. Finally, from the microfacies analysis,
depositional environment can be revealed.
Lecturer, Dr. Department of Geology, University of Yangon
130
Figure (1) Location and accessibility map of the study area
131
Microfacies Analysis Of the Linwe Formation
The rocks of the Linwe Formation can be classified into six
microfacies based on the particle component, texture and sedimentary
structure in this investigated area. These microfacies together with their
allochem and orthochem content are plotted as shown in figure (2).
Figure. (2) Petrographic plots of the Linwe Formation based on the orthochem
allochem content.
132
Microfacies 1: Lime mudstone (L-1)
This microfacies consists of planar laminated (lamination is maximum
4cm), grey, thin to medium bedded argillaceous limestone with bluish grey
calcareous shale (Figure.3). The rocks of this microfacies occupy the lower
and middle part of measured section. The rock consists of dense, dark grey,
micrite and argillaceous lime mudstone.
There is no evidence for high current energy. High micrite
accumulation reflects low energy condition. The fact that the rock has lack of
fossil evidence indicates the environment of deposition is not hospitable for
marine life. Most fine-grained sediments are largely deposited by suspension.
Thinly, flat laminated limestone and its fine-grained nature of this facies
strongly suggests slow rate of sedimentation in low energy quiet water
environment.
Microfacies 2: Bioclastic lime mudstone (L-2)
It is composed of grey to buff coloured, medium bedded, thickening
upward in bedding and lamination, argillaceous limestone with shale.
Thickness of intercalated shale lamination is about 3mm to 5mm.
The rock comprises bioclasts such as ostracods 4-5%, crinoids 3-5%
and thin bivalve shells 1% by volume which are well packed by
microcrystalline carbonate mud (Fig.4). Bioclasts are filled with sparry calcite
mosaic. Their size is 0.1mm in diametre. Bioclasts are moderately to well
sorted. Interparticle pores are filled with microcrystalline carbonate mud same
as matrix. Microstylolites are locally common; along which clay materials are
observed. Scattered pyrite bits are 0.025mm to 0.075 mm in size containing
less than 1% by volume. They are idiotopic fabric with rectangular outline
(Figure.5).
High content of lime mud is evidence for lower energy condition.
Parallel lamination indicates the low energy condition and medium bedded
nature shows slow rate of sedimentation. Limestone with intercalated
argillaceous layer suggests the alternate deposition of clastic rich sediments
and carbonate rich sediments with fluctuation in current energy condition.
Bioclasts are possibly derived from up slope.
133
Microfacies 3: Biointraclastic wackestone (L-3)
This rock is made up of buff coloured, thinly bedded very finegrained, limestone. Argillaceous content is higher upward. Slump feature is
common.
This rock consists of bioclasts about 1-2% by volume and slightly
lithified intraclast 20%. Intraclasts are 1mm in maximum diameter. They are
roughly equidimensional, not well sorted, but sub-rounded in appearance and
clayey material coated (Figure.6). Matrix is bioclastic mudstone. Intraclasts
and matrix are same. Interparticle pores are filled with microcrystalline calcite
mud.
High micrite accumulation reflects low energy condition. Previously
lithified intraclasts are transported by current from up slope and probably
deposited in unstable inclined slope. Subrounded appearance of intraclasts
shows slight wave energy condition.
Microfacies 4: Bioclastic wackestone (L-4)
This rock consists of light grey to pinkish or purple, medium to thick
bedded, fine-grained, poorly jointed, wavy discontinuous laminated
argillaceous limestone. Phacoidal structure is also developed on bedding
surface. Crinoid fragments are locally scattered on weathered surface. This
microfacies is widely distributed through out the measured section. Nodular
bedding is common. The rock consists of bioclasts such as echinoids up to
20%, ostracods about 4-10%, gastropods 10%, brachiopod 5% by volume.
Bioclasts are not sorted in size and shapes, but coarse. Interpartical pores are
filled with microcrystalline carbonate mud. Internal sediments of the bioclasts
is same as micrite matrix. Type of bioclasts are diverse.
134
Fig. 3 Laminated grey, thin
to medium bedded
argillaceous limestone
with bluish grey
calcareous shale, 21°
05' 00" N, 96° 50' 40"
E, 0.8 km SE of Kywe
daung hill
Fig. 4 Well preserved
ostracod shells (o) are
well packed by
microcrystalline
carbonate mud (m) in
bioclastic lime
mudstone microfacies
(MF-2) PPL. (S.No.A
12)
Fig. 5 Pyrite (arrow) with
rectangular outline
scattered in bioclastic
lime mudstone
showing reducing
environment. PPL.
(S.No. B.7)
135
Fig. 6 Previously
lithified
intraclasts (i) which are
same
as
matrix
in
biointraclastic wackestone
microfacies in lower part of
measured section. PPL.
(S.No . A.29)
Bioclast which is aggraded neomorphosed. Brachiopod shell which is
degraded neomorphosed. is shown in (Fig. 7). Drusy calcite cement filled the
interparticle pores. Amplitude of microstylolite ranges from 0.1mm to 0.3
mm. This microfacies can be correlated with S.M.F 9 (Wilson, 1975).
Low energy condition is suggested by high content of lime mud
accumulation. Wavy discontinuous argillaceous laminations indicate slight
current condition within sufficient supply of fine clastic sediments by
intermittent storm. Diverse shelly fauna reflects oxygenated normal marine
salinity with adequate water circulation. The fact that unbroken shells are
more than broken bioclasts suggests that shells were not influenced by wave
action and they are well packed by micrite.
Microfacies 5: Bioclastic-lithoclastic packstone (L-5)
This rock comprises buff coloured, micaceous, soft, thin to medium
bedded poorly exposed limestone with shale and silt intercalation.
This rock composed of bioclastic lithoclasts fragments 50% by volume
and previously lithified lithoclastic fragments. (Fig.8) Bioclasts and lithoclasts
are coated, subrounded and poorly sorted. Size of bioclastic grains up to
0.2mm in diameter. This microfacies can be correlated with S.M.F 4 of by
Wilson, 1975.
Dominant particles are of high energy environment and have move
down to local slopes to be deposited. Coarse shell fragments may be derived
from up slope by slight energy current velocity. Abundant occurrence of
lithoclasts in various size and rock type strongly suggests the rocks are made
up entirely of marine talus and coarser debris probably derived by submarine
slumping or turbidity current.
136
Microfacies 6: Bioclastic packstone (L-6)
This rock is greenish to pinkish, medium to coarse crystalline, thick
bedded wavy laminated, poorly jointed, nodular limestone. Crinoids stems
commonly occur on the bedding plane and weathered surface. This
microfacies distributes only in the upper part of measured section.
The rocks composed of bioclasts more than 50% by volume. Matrix is
microcrystalline carbonate and clayey materials. Crinoids are most abundant
bioclasts in this microfacies. Some bioclastic grains are 0.2mm in diameter.
Bioclastic grains are poorly sorted, rounded. Grains are showing syntaxial
overgrowth, later subjected to micritisation (Figure.9). This microfacies
coincide with S.M.F 5 by Wilson, 1975.
In this microfacies with high diversity and large amount of fauna
strongly suggests good current circulation and normal marine salinity with
well oxygenated condition. Wavy discontinuous lamination reflects the slight
current condition with intense wave activities above normal wave base. Some
coarser shell fragments were probably derived from up slope by current
transportation.
Fig. 7 Degrading neomorphism (d) in
brachiopod shell fragments (b)
in bioclastic wackestone, lower
part of measured section PPL.
(S.No. A2)
Fig. 8 Lithoclast(l), (Fig.A) and
corroded bioclastic
lithoclast(b), (Fig.B) in
bioclastic lithoclastic
packstone microfacies.
Notice that there is no grain
to grain contact showing lack
of deep burial
compaction.PPL.(S. No.
A40)
137
Fig. 9 Bioclastic grains cemented
by syntaxial overgrowth
(s),later micritization occur.
Bioclastic packstone
microfacies.
PPL.(S.No. A.44)
Microfacies Association and Depositional Environment of the Linwe
Formation.
The rocks of the Linwe Formation can be categorized into six
microfacies. These microfacies are grouped into four main facies associations
for four different depositional environments, such as, basin, open sea shelf,
deep shelf margin and fore slope environment respectively. Table (1)
describes-microfacies association, their depositional environment and
respective characteristic features. Table (2) shows four main depositional
environments identified by microfacies analysis of the Linwe Formation on
the base of grain type, physical, biologic and sedimentary structure.
138
Table - 1
Depositional environment and characteristics features of the Linwe Formation
Micro
facies
No
Microfacies
1.
Lime mudstone
2.
Bioclastic lime mudstone
Environment
Basin
Characteristic features
- Lime mudstone with some calcisilt
- Low energy, rhythmic bedding
- Some shale, fine clastic
4.
Bioclastic wackestone
Open sea shelf
- Wackestone, diverse fossil, nodular bedding
3.
Biointraclastic wackestone
Deep shelfmargin
- Slump, talus
- Regular bedding
- Low energy
- Slightly lithified intraclast
- Organism rolled particle
5.
6.
Bioclastic-lithoclastic
packstone
Foreslope
- Lime sand,
- Abundant organism
- Lithoclast
- High energy
139
Table 2. Characteristic Features of Depositional Environment for
microfacies of the Linwe Formation (based on, Wilson, 1975 and
Reckmann & Friedman, 1981)
Summary And Conclusion
140
Summary and conclusion
The rocks of the Linwe Formation can be classified into 6 microfacies
which fall into 4 different facies association. Lime mudstone and Bioclastic
lime mudstone are probably deposited in basin environment. Characteristic
feature of basin environment possessed in these microfacies are low energy
lime mudstone, rhythmic bedding, some shale and fine clastics.
Bioclastic wackestone having the characteristic features of diverse
fossil, nodular bedding, discontinuous wavy lamination, is accumulated in
open sea shelf environment.
Biointraclastic wackestone. May be deposited in deep shelf margin due
to the presence of regular bedding, slump, low energy condition and rolled
particle organism and slightly lithified organism.
Foreslope facies association contains bioclastic-lithoclastic packstone
and bioclastic packstone. These microfacies posses the characteristic features
such as lime sand, abundant organism, lithoclast, high energy condition.
Acknowledgements
The author would like to express her sincere thanks to Professor Dr Day Wa Aung,
Head of Dpartment of Geology, University of Yangon for his permission to present this paper,
Professor Dr Win Naing, Pro-Rector, University of Yangon and part-time Professor U Myitta,
for their invaluable instructions, suggestions, guidance as well as critical reading of the earlier
version of the manuscript.
References
Adams,A.E. and Mackezie, W.S., (1998), A colour Atlas of carbonate Sediments and Rocks
under the Microscope, Manson Pub, 180p.
Dunham, R.J., (1962) Classification of carbonate rocks according to depositional texture. In
Ham, W.E ed. Classification of carbonite Rocks: Am.Ass. Pet. Geol. Mem.
1.p.105-121.
Folk, R.L., (1965). Some aspects of recrystallization in ancient dolomitization and limestone
diagenesis: Soc.Econ. Paleont. and Mineral. Spec. Pub. 18, p.14-48.
Horowitz, A.S. and Potter, P.E., (1971), Introductory Petrography of Fossils, Springer Verlag, 302p.
Pettijohn, F.J., (1956) Sedimentary Rocks. 2nd ed., Oxford Book Co.718p.
Reckmann,A. and Friedman,G.M, (1981). Exploration for Carbonate Petroleum Reservoirs: A
Wiley Interscience Publication, p.18-20.
Wilson, J.L., (1975). Carbonate Facies in Geologic History: Spinger-Verlag, Berlin,
Hidelberg, Germany. 374p.
Sedimentological Aspects of the Turbiditic Division of
the Loi-an Group, Thazi and Kalaw Townships
Me Me Thein1, Myitta2, Zaw Win3
Abstract
The turbidites of the Loi-an Group are well exposed along the lower reaches
of Thapanbauk chaung, Gegauk chaung and Ponlon chaung, west and east
of Kyatsakan, around the Shweminbon hill, along the railway section
between Sindaung and Myindaik, and along the range of Manawhla, north
of Kalaw. In the stream section, interbedded nature of sandstonemudstone
dominated turbidites, minor amount of limestone and siltstone are well
exposed. The distinct characteristic feature is the occurrence of bottom
sedimentary structures such as flute, load and groove-casts in most of the
sandstone beds of turbiditic nature. The beds are folded and highly tilted,
some display overturned in nature. Seven lithofacies are recognized; (1)
massive, thick-bedded sandstone facies (2) thinly interbedded sandstoneshale facies (3) horizontal, low-angle planar laminated sandstone faices (4)
medium to thick-bedded sandstone with crude cross-bedding facies (5)
mudstone facies (6) thinly interlayered sandstone-marls facies and (7) marls
facies. The three facies associations are upper fan facies association, middle
fan facies association and lower fan facies association. The three facies
associations are assigned to as the detlta-fed submarine fan system.
Key words: Turbiditic Division, Loi-an Group
Introduction
The study area is located in the western margin of the Shan Plateau,
Thazi and Kalaw Townships (Fig.1). The turbiditic division of the Loi-an
Group embraces the well-bedded sandstone mudstone turbidites which has
been known as the Shweminbon Group of Fay Lain et al. (1972-1976), Ma-U
bin turbidites of Garson et al. (1976), Kunge-yo Formation and Gegauk
Formation of Khin Maung Win et al. (1980), Thapanbauk Beds and Gegauk
Formation of Khin Maung Latt (1980), Pinmon Beds, Tayaw Formation and
Gegauk Formation of Saw Pe (1982) and Shweminbon Formation and Gegauk
Formation of Kyi Soe (2000).
1. Lecturer, Dr, Department of Geology, University of Dagon.
2. Part-time professor, Department of Geology, University of Yangon.
3. Professor and Head, Dr, Department of Geology, University of Sittwe.
142
Figure (1) Location map of the study area
The turbidites are well exposed in the western part of Shweminbon
range (4635'), in the upper part of the Law chaung, Taungbet chaung,
Shweminbon chaung and along the route of Taungbet village to Shweminbon
taung. A monotonous sequence of shale and mudstones with calcareous
sandstone are predominantly exposed along the Gegauk, Thapanbauk, Minhla
and Ponlon chaung. Minor amount of carbonate rock units are well exposed at
the area between Sindaung and Myindeik station.
The siliciclastic units of turbiditic division are mainly composed of
sandstone, mudstone, siltstone, shale and a few amounts of argillaceous
143
micritic limestone and rudaceous limestone. The classical turbidites showing
interbedded nature of sandstone and shale with Bouma's sequence are well
exposed. Primary sedimentary structures, such as graded-bedding, crossbedding and worm tracks are seen in the sandstone beds. Some of the lower
beddings of sandstone display sole marks, flute casts, groove casts, load casts
and animal trails (Fig.2).
(a)
(b)
(c)
Figure(2) Sole Marks found in Thapanbauk chaung section (a) Flute-casts,
broad and somewhat ill-defined, (b) Finely-textured, closely packed
load-casts, (c) Groove and striation casts on base of sandstone bed,
Clastic Facies Analysis
There are seven major clastic facies which can be interpreted from the
lithologies, textures, primary sedimentary structures, fossil content and
stratigraphic position. The observed lithofacies are shown in (Fig.3). The
measured section of the turbiditic division is along the Gegauk chaung (Fig.4).
(a)
(b)
(c)
144
(d)
(e)
(f)
(g)
Figure(3) Lithofacies of the turbiditic division (a) Massive, thick-bedded
sandstone facies, (b) Thinly interbedded sandstone-shale facies, (c)
Horizontal, low-angle planar laminated sandstone facies, (d)
Medium to thick-bedded sandstone with crude cross-bedding facies,
(e) Mudstone facies, (f) Thinly interlayered sandstone-marls facies,
(g) Marls facies,
(Facies.1) Massive, thick-bedded sandstone facies
This facies consists of by fine to medium-grained, purplish-brown or
grayish-brown colored sandstone. The Bouma division T a is well developed
but T b or T e sequences are followed in some horizon. Many of the sandstone
beds usually show flat, scoured bases and normal grading, and are
structureless and sometimes parallel laminated and cross-laminated.
Figure (4) Sedimentological log of the turbiditic division (along Gegauk
chaung section, 2 miles east of Kyatsakan village).
145
146
(Facies.2) Thinly interbedded sandstone-shale facies
This facies is characterized by fine to medium-grained, purplish brown
colored, thinly planar laminated and very small-scale ripple cross-laminated
sandstones interbedded with evenly laminated carbonaceous muddy shale.
Thinly planar laminated and small scale ripple cross-laminations with sharp or
transitional are found in a single bed. Sedimentary structures within the
sandstone units are predominantly horizontal laminae overlain by ripple cross
laminae. This is in turn is overlain by parallel laminated shales. Each
sandstones-shale couplet is interpreted as Bouma T bc -T bce sequence.
(Facies.3) Horizontal, low-angle planar laminated sandstone faices
This facies consists of thin to medium bedded, bluish-grey colored,
fine to medium-grained, horizontal laminated and low-angle planar laminated
sandstones. The average thickness of beds is about 20-30 centimeters. The
thinly planar laminated and low-angle planar laminations are sharp or
transitional in a single bed.
(Facies.4) Medium to thick-bedded sandstone with crude cross-bedding
facies
Medium to thick-bedded, fine to medium-grained, purplish-brown
sandstone (25-35 cm) thick with crude cross-bedding is characterized in this
facies. Complex wave ripple cross-laminae with locally hummocky crossstratification are common. Minor convolute laminae and interacting
interwoven cross-lamination of complex wave formed ripple pattern occur
within sandstone beds. Sandstone beds usually show flat, locally scoured
bases and normal grading. Sole structures (groove-cast, flute cast and load
cast) are occasionally observed.
(Facies.5) Mudstone facies
Bluish-gray or greenish-brown mudstone is the most conspicuous in
this facies. Calcareous and ferrugenous mudstone concretions mostly occur in
the mudstone intervals. The abundant greenish-brown, indurated mudstone
nodules and concretion horizons are also found. The size of nodules range
from (0.3×2)cm to (0.5×3) cm is plano-convex to biconvex shape. These
mudstone are defined are T e unit of Bouma sequence.
(Facies.6) Thinly interlayered sandstone-marls facies
This facies mainly consists of fine to medium-grained, bluish-grey
colored, sandstone interlayered with marls. Vertical burrows (Skolithos) and
147
horizontal burrows (Planolites) are common in sandstone bed. The most
distinctive are Planolites sp. which are largely parallel to bedding and are
essentially straight, unbranching tubular burrows. Vertical burrows present as
tubes, circular in cross-section. They are unlined or very thinly mud lined,
straight to gently curved. Bivalve shell debris is occasionally present.
(Facies.7) Marls facies
This facies is characterized by bluish-grey colored marl with abundant
pelecypod shell. The bivalve shell debris are randomly oriented indicating that
the deposits are accumulated below wave base. Vertical burrows (Skolithos)
and horizontal burrows (Planolites) occur throughout the section.
Facies Association
In the present study area, the sedimentary facies of the turbiditic
division can be grouped into three facies associations. They are Facies association. 1 - Upper fan facies association
Facies association. 2 - Middle fan facies association and
Facies association. 3 - Lower fan facies association.
(Facies association. 1) Upper fan facies association
In the upper fan facies association, inter-channel slope deposits of
thinly-interbedded sandstone-shale facies, subaqueous levee deposits of
horizontal and low-angle planar laminated sandstone facies, feeder channel fill
deposits of medium to thick bedded sandstone with crude cross-bedding facies
and massive, thick-bedded sandstone facies are found.
The upper fan has the channel and levee system and is largely a
sediment by-pass area. Relatively high velocities maintained during the main
part of the flow, turbidity currents deposits the very coarse sands and gravel in
the channel, to form thick, structureless or orderly graded beds.
Most of an individual turbidity flow is confined to the channel in the
proximal fan, but the upper, more dilute part of the flow may spill out of the
channel laterally.
(Facies association. 2) Middle fan facies association
Middle fan facies association is characterized by an abandoned fan
lobe deposits of thinly-interlayered sandstone-marls facies and marls facies.
148
Most deposition, especially of sand, occurs on the lobes that develop
in the mid-fan as flow velocities drop and the channel system breaks down.
The lobe may be dominated by massive, thick-bedded, high-density turbidites
or display more clastic turbidites and interbedded hemipelagic shales. Sandshale ratios are highest within the core or apex of the lobe, but decrease
markedly towards the lobe margins. The channel at the top of the lobe will
have an erosive base and contains turbidites which may flow a fining-upwards
pattern as the lobe is abandoned in favour of another lobe building up
elsewhere. This situation favors the deposition of marls facies.
(Facies association. 3) Lower fan facies association
Mudstone facies occur mainly on the lobe fringe of distal ramp
turbidite of the lower fan. In the lower fan areas, thin bedded turbidites and
most of the hemipelagic deposits are present. The lower fan is an apron of
fine-grained distal turbidites deposited by unconfined flows. Turbidity
currents which flow along the upper fan channel and across a mid-fan lobe
may eventually reach the lower fan. By the time they have reached this outer
area, only fine sand, silt and clay will be deposited on the lower fan.
Hemipelagic sediments are proportionally more significant in the lower fan
area as the volume of turbidites decreases distally. Therefore, mudstone facies
was deposited in the lower fan area where mud settles out of suspension.
Depositional Environment
In the turbiditic division, the three facies associations correspond to
specific environment of a delta-fed submarine fan system (Fig.5).
Delta-fed submarine fan is constructed at the mouth of shelf marginal
area as a result of falling of relative sea-level. It comprises one or more feeder
channels or canyons, tributary and distributary channels, abandoned half-filled
channels, slump and slide scars and blocks, debris flow masses, broad channel
levees, lobes built up at the end of channels and distributaries, and relatively
smooth or current moulded interchannel and interlobe area.
149
Figure (5) Block diagram of Delta-fed Submarine Fan.
The upper fan is characterized by a leveed channel, which is slightly
curved. The middle fan is made up of individual supra-fan lobes, which
migrate laterally. The inner part of the supra-fan is characterized by shallow,
non-leveed, braided channels. The outer part of the supra-fan lobe is smooth
and merges into the smooth lower fan.
Conclusion
Turbiditic sedimentary rocks are exposed in the vicinity of the
Thapanbauk, Nampandet and Gegauk stream areas and at the deep gullies
along the western foothills of Shweminbon Range.
The classical turbidites shows monotonous alternation of the sharpbased sandstone and interbedded mudstone with Bouma sequence in the
turbiditic division.
Minor amount of carbonate rock units are well exposed at the area
between Sindaung and Myindeik station.
The classical turbidites are correspond to the deposits of delta-fed submarine fan system constructed at the mouth of the shelf-marginal area. The
upper fan environment consists of (1) feeder channel fill deposits of massive,
thick-bedded sandstone facies and medium to thick-bedded sandstone with
crude cross-bedding facies: (2) subaqueous levee deposits of horizontal and
low-angle planar laminated sandstone facies and (3) inter-channel slope
deposits of thinly-interbedded sandstone-shale facies. The middle fan
environment contains abandoned fan lobe deposits of thinly interlayered
sandstone-marls facies and marls facies. Lobe fringe of distal ramp turbidites
of mudstone facies are deposited in the lower fan environment.
150
Acknowledgement
I am specially grateful to U Myitta, Part-time Professor of Geology Department,
University of Yangon and Dr. Zaw Win, Professor and Head of the Department of Geology.
Sittwe University for providing valuable advices and critical comments during my research
work.
References
Anderton, R., (1985). Clastic facies models and facies analysis. In: P.J. Brenchley & B.P.J,
Williams, Recent developments and applied aspects; Sedimentology
Blackwell, Oxford, London (31-48)
Bhattacharya, J.P., and Walker, R.G., (1992). Deltas: In, Walker R.G and James N.P.eds.
Facies model; response to sea-level change. Geol. Asso. Can., Geotext 1.
P.157-178.
Bouma, A.H., Normark, W.R., and Barnes, N.E. (Eds), (1985), Submarine fans and Related
Turbidite Systemes, 351 pp. Springer-Verlag, New York.
Coleman, J.M., and Prior, D.B., (1980). Deltaic sand bodies; American Association of
Petroleum Geologists Education Course note series.
Elliott, T., (1978). Deltas. In: Sedimentary Environments and Facies (Ed. By H.G. Reding),
pp.97-147. Blackwell scientific Publications, Oxford.
Heller, P.L., and Dickinson, W.R., (1985). Submarine ramp facies model for delta-fed, sandrich turbidite systems; American Association of Petroleum Geologists
Bulletin, vol.69, pp.960-976.
Khing Maung Win, Khin Maung Latt, Than Naing, Zaw Thet, Myittar and Myint Lwin Thein.
(1980). Stratigraphy of the northern part of the Kalaw-Pinlung Basin
(Jurassic-Cretaceous) of the Southern Shan Region, Burma. Unpublished
report, University of Yangon, 44p.
Lowe, D.R., (1982). Sediment gravity flow II; Depositional models with special reference to
the deposits of high-density turbidity currents; Journal of Sedimentary
Petrology, vol.52, pp.279-297.
Me Me Thein, (2011). Sedimentology of the Loi-an Group, in the western margin of the Shan
Plateau, Thazi and Kalaw townships, Southern Shan State.
Reading, H.G., (1996). Sedimentary Environments: Processes, Facies and Stratigraphy,
Blackwell Sciences Publications, 3rd. edn., Oxford, 668 pp.
Reineck, H.E., and Singh, J.B., (1980). Depositional Sedimentary Environemnts: SpringerVerlag, New York, 540p.
Van Wagoner, J.C.et al., (1990). Siliciclastic Sequence Stratigraphy in Well Logs, Cores and
Outcrops. American Association of Petroleum Geologists, Methods in
Exploration Series No.7, 55p.
Silurian Transgressive Rocks in the Linwe-Pegin and
Yegyanzin-Wabya Areas, Shan State (south)
Yin Min Htwe1, Myitta2, Zaw Win3
Abstract
The present study area constitutes the northwestern and southern part of the
Pindaya Range, Shan State (south). The Silurian Mibayataung Group
consists of distinctly phacoidal (nodular) limestones of Linwe Formation
and whitish grey shales of Wabya Formation. Lithofacies and microfacies
of the Linwe Formation exposed in the Linwe-Pegin area and YegyanzinWabya area are studied. The limestones from Linwe-Pegin area are purple
phacoidal limestone; graptolite shales; limestones with argillaceous seams;
second graptolite shales; limestones with pressure solution; siltstones,
shales and mudstones units and gray phacoidal to typical nodular
limestones. Crinoidal limestones, cephalopod limestones and nodular
(phacoidal) limestones are included in the Yegyanzin-Wabya area. Fourteen
microfacies types from Linwe-Pegin area and eleven microfacies types from
Yegyanzin-Wabya area are described, most of them fitting one of the
categories of the standard microfacies (SMF) concept. The sediments from
Linwe area show much mutual replacement of silica and calcite, inferring
multiple stages of varying pH conditions. The major element compositions
of 34 representative limestone samples from Linwe-Pegin area and
Yegyanzin-Wabya area were selected for analyses. A shallowing and
subsequent deepening phase of the depositional environment is indicated,
the entire development reflecting a continuous, rather rapid relative rise of
sea level. The nodular structure in the limestones are mainly confined to
Ordovician-Silurian (Paleozoic) and Jurassic-Cretaceous (Mesozoic) is
indicative of major sea level transgression. Many of the transgressive
surfaces are marked by fossil diversity in measured stratigraphic section. At
some horizon, the rate of transgression increased, resulting in the shutdown
of carbonate production and the deposition of silty mudstones and shales in
the upper horizon.
Key words: Silurian, Linwe-Pegin, Yegyanzin-Wabya, transgressive
Introduction
The marine transgressive Silurian Mibayataung succession of the Shan
State (south) is divided into 2 formations, namely, the Linwe Formation
(middle Llandovery) and Wabya Formation (middle Llandovery), extends
over the Shan State. This research is part of a sedimentological study of this
1. Dr., Lecturer, Geology Department, Dagon University
2. Part-time Professor, Geology Department, University of Yangon
3. Dr., Professor and Head, Geology Department, Sittway University
152
limestone unit and focuses on local and regional sea level history. The Linwe
Formation is well exposed from Pegin in the north to Kyauknget in the south
on topographic map no. 93C/12 and Waya Formation is well exposed in the
south of Sale-in to Wabya Hill (5408') and Pothudaw pagoda Hill on
topographic map no. 93D/9.
Materials & Methods
The petrographic study was based on 200 samples obtained from the
two studied areas. The geochemical data of 34 representative limestone
samples are based on four sections from Linwe-Pegin area and three sections
from Yegyanzin-Wabya area.
Lithofacies of the Linwe-Pegin area
There are five measured section from Pegin village to Kyauknget
village. Exposures of Silurian rocks units are mainly occurred from west to
east and at the Kyauktaw village. Five distinct lithofacies of the limestones of
the Linwe-Pegin area is shown in (Table 1).
Table (1) Distinct lithofacies can be observed in Linwe-Pegin area
Exposure
Description
Purple phacoidal limestone
 the most prominent in the lowest part of the
Linwe Formation.
 Large amount of crinoids fragments are
scattered on the weathered surface.
 Occasionally, bioturbated horizon with
numerous fossil fragments can be observed.
Graptolite shale
 more prominent at Pegin road cut section.
 is whitish to bluish grey colored, micaceous
and sometimes very hard.
 Many graptolites are present in this shale
unit but the preservation is not good as
Wabya graptolites.
Limestone and argillaceous seam interbedded
 mainly observed at the Pegin road cut
section and Linwe section.
 Buff to reddish color micaceous siltstone
153
Exposure
Description
and shale unit is sandwiched
 This lithofacies is repeated again appeared
at the Pegin section which is 15-19 m
thickness and at the Pegin road cut section
which is 10-12 m.
Siltstone, shale and mudstone lithofacies
 more prominent in the Linwe village and
Kyauktaw monastery in which Silurian
trilobites (Calymene sp.) are encountered.
 The siltstone can be observed as a
transitional rock type.
 The whitish grey shales grade into
micaceous siltstone is observed at the Pegin
area.
Gray phacoidal to typical nodular limestone
 can be observed near Linwe monastery in
which gray phacoidal to typical nodular
limestone are encountered.
 This lithofacies ranges in thickness from 1to
80 m and in lateral extent from 60 to 1500
m.
 It is composed of multiple phacoidal bodies
made up of individual beds of 0.3 to 0.8 m
thick.
Lithofacies of the Yegyanzin-Wabya area
There are three measured sections, namely, the Shanywa section,
Wabya base section and Sale-in section in which six distinct lithofacies are
encountered (Table 2).
154
Table (2) Distinct lithofacies can be encountered in Yegyanzin-Wabya area
Exposure
Description
Limestones with wavy to lenticular beds
 only observed at the base of the Shanywa
section.
 are purple, fine to medium-grained
 Some of them are very resistant and
display wavy to lenticular pattern.
Limestones with wavy argillaceous seams
 is mainly observed in Wabya base section
and Shanywa section.
 occurs as thin to medium beds which are
poorly resistant.
 The rock is fairly fossiliferous and
sometimes interlayered with wavy
argillaceous seams.
Limestone and marl interbedded
 occurs in Shanywa section.
 is thin to medium-bedded, mediumgrained and interbedded with marl that is
yellow in color on fresh surface.
Medium
to
thick-bedded
limestones
interbedded with argillaceous layers
 occurs in Shanywa section
 occurs as medium to thick beds which are
resistant with argillaceous layers.
 The weathered surfaces are light to dark
gray or brown. The fresh surfaces are
medium gray.
155
Exposure
Description
Purple limestones and impure limestones
 is mainly observed in the Sale-in section.
 is found as thickening-upwards beds
 The fresh surface is pink to purplish red,
and displays crinoidal limestones
interbedded with argillaceous bioclastic
limestone.
Argillaceous limestones and siltstone interbeds
 occurs in Sale-in section.
 are fine-grained, dark reddish brown on
weathered surface while purple to light
reddish brown on fresh surface.
 The rock is resistant and occurs in steplike outcrops.
Microfacies of Linwe-Pegin area
This microfacies is a grain-supported bioclastic packstone (Fig. 1a).
The bioclastic material occupies about 30-50 percent of the slide surface area,
some grains show sign of welding by pressure solution. Crinoids,
brachiopods, echinoid, bryozoans constitute the majority of the larger
bioclasts, while the smaller particles are made up of similar composition
together with sponge, ostracod, gastropod, tentaculites, cephalopod and
unidentifiable fragments. The interstitial spaces are filled by high
concentration of broken fine crinoids arm plates.
Ostracod packstone
This microfacies is a grain-supported packstone. Ostracods are set in
the reddish brown clayey matrix (Fig.1b). The bioclastic materials are almost
entirely of ostracod and cover 25-60 percent of the slide surface area. There is
a sharp reduction in the frequency of crinoids, brachiopods, trilobites, sponge
spicules and calcispheres. The ostracod usually occurs as unbroken and
156
unabraded single valves, but there are also some broken but unrounded
fragments and some articulated complete shells.
Argillaceous crinoidal packstone
This microfacies is a grain-supported argillaceous crinoidal packstone
masked in the iron-oxide fine-grained matrix (Fig.1c). The bioclastic
fragments are almost entirely crinoid arm plates, incipiently unsorted, and
oriented. There is a sharp reduction in the frequency of ostracod valves,
brachiopods, sponge spicules and calcispheres. Post depositional disturbance
of the fine-grained matrix, shown by the irregular and often spiral distribution
of the crinoid in some slides, suggest reworking by scavengers or currents.
Nodular bioclastic packstone
This microfacies is a grain-supported nodular bioclastic packstone
with 20-40 percent of bioclastic materials (Fig.1d). Fossils consist mostly of
ostracod valves with some crinoids and trilobites, usually as single unbroken
valves, but small broken ostracod fragments are also very common. These
may have been broken by scavengers or currents. Fine-grained detrital quartz
are scattered along the micronodular argillaceous seam.
This microfacies is a mud-supported bioclastic wackestone with
scattered, 'floating,' relatively large fragments of crinoids and cephalopods,
with their central canals and cavities filled with microcrystalline calcite
cement (Fig.1e). The bioclastic materials accounts for about 15-25 percent of
the slide surface area and some specimen contains ostracod valves, crinoids
plates and brachiopod shell or trilobite fragments. Most of these large crinoids
appear not to have been disturbed after their deposition, with the exception of
some local flattening produced by compaction.
Argillaceous bioclastic wackestone
This microfacies, mud-supported argillaceous bioclastic wackestone, is
similar to microfacies 5, in that the largest bioclastic fragments are trilobite,
crinoids stem and the smaller particles are the similar composition with
calcisphere. The bioclastic materials account for about 10-25 percent of the
slide surface area and some grains show microboring (Fig.1f). The crinoids
stem is bored by burrowing organism and later filled by iron-oxide.
Subangular to rounded fine-grained detrital quartz are scattered throughout the
matrix.
157
Nodular bioclastic wackestone
This microfacies is a mud-supported nodular bioclastic wackestone
which contains 10-20 percent of bioclastic materials floating within the
nodules (Fig.1g); size variation of these nodules from sand-sized to larger than
2 mm are dominated. The bioclastic fragments are almost entirely crinoidal
and broken unidentified shell fragments incipiently sorted and show traces of
abrasion. Some of the bioclastic nodules are oriented and others are
disoriented.
Dolomitized lime mudstone
This microfacies is a mud-supported dolomitized lime mudstone in
which dolomite forms a mosaic of idiomorphic to xenomorphic crystals of
averaging 0.025 mm in size (Fig. 1h).
Argillaceous lime mudstone
This microfacies is a mud-supported argillaceous lime mudstone with
less than 5 percent bioclastic materials (Fig.1i). The bioclastic fragments are
limited to crinoid plate, ostracod valves and trilobite fragments. The matrix is
crypto to microcrystalline, light brown to dark brown calcite, colored by
pyrite and organic matter. Angular fine-grained detrital quartz are scattered
throughout the matrix. Pyrite particles are more common in this microfacies
than in any other within the normal microfacies group.
158
Microfacies of Yegyanzin-Wabya area
Encrinite
The rocks in this microfacies are made up entirely of crinoid plates and
ossicles (Fig.2a). The bioclastic material accounts for about 50-60 per cent of
the slide surface area and some grains show signs of welding by pressure
solution. It is densely packed and grain-supported fabrics. Bioclasts are poorly
sorted but may be moderately rounded. The crinoid plates and columnals
frequently exhibit pressure welding and incipient recrystallization with
syntaxial growth along the fragment edges forming clear spar.
Crinoidal packstone
This microfacies is a grain-supported crinoidal packstone with finer
silt sized matrix (Fig.2b). The larger organic debris is dominated by fragments
of crinoids, brachiopods and bryozoans. The crinoid plates and colunmals
exhibit as unsorted fragments and crystal diminuation along the cleavage
plane. Brachiopod valves and spines are widespread throughout the samples
studied. Bryozoans tend to be restricted to the coarser clasts, and some occur
as complete fronds.
Argillaceous crinoidal packstone
This microfacies is similar to microfacies 2, crinoidal packstone, in
that the organic fragments are almost entirely crinoidal and bryozoans with
incipiently sorted and abraded (Fig.2c). The bioclasts show a high degree of
roundness and apparent sphericity, and may cover 60 to 70 percent of the
slide's surface area. However, the interstitial spaces are filled by argillaceous
material, iron oxide pigments, and fine-grained detrital quartz and locally by
crystalline calcite. Much iron oxide pigment has penetrated the cellular
networks of the crinoid fragments and stained them. Locally, small interstitial
159
areas are filled with broken, fine, organic fragments including many bryozoan
fragments.
This microfacies is a grain-supported fabric consisting of 35 to 40 per
cent of bioclastic materials set in the matrix (Fig.2d). The grains consist
mainly of crinoid complete columnals, calyx plates and broken fragments of
bryozoan, brachiopod valves, occasional sponge spicules and rare ostracod
tests. None of these components shows any sign of abrasion. Interstitial spaces
are filled with fine-grained detrital quartz and iron oxide pigments with very
few small bioclastic fragments.
Argillaceous bioclastic packstone
This microfacies is grain-supported with angular to subrounded detrital
quartz grains within the matrix (Fig.2e). The bioclasts show apparent
roundness and sphericity, and may cover 50 to 70 percent of the slide surface
area. They include fragments of crinoid plates and ossicles, echinoid spines,
brachiopod shells and spines, calcareous spicules and bryozoans. Interstitial
spaces are filled with fine-grained detrital quartz and iron oxide pigments with
very few small organic fragments.
Ferrugenous crinoidal packstone
This microfacies is a grain-supported fabric in which all of the
fragments are crinoids arm plate and ossicles (Fig.2f). The crinoids may cover
40 to 50 percent of the slide's surface area. Some of the crinoid plates are
replaced by chert. Interstitial spaces are filled with fine-grained detrital quartz
and later filled secondly iron-oxide. Ferrugenous materials that account for
about 10 to 25 per cent are scattered as a random fashion throughout the finegrained matrix.
Intraclastic packstone
This microfacies is a grain-supported intraclastic packstone which
consists of 20-25 percent of intraclasts and some larger bioclastic fragments
set in the fine-grained matrix (Fig.2g). Only one type of unsorted biomicrite
intraclasts is noted in this microfacies. Large bioclastic fragments are almost
entirely well-cemented original shell of cephalopods, incipiently sorted and
traces of abrasion.
160
Peloidal packstone
This microfacies is a grain-supported peloidal packstone with
abundant pellets of unknown, but possibly fecal origin (Fig.2h). The pellets
are uniformly small particle size and consistent in shape of the grains. A
brown color in reflected light also favours a fecal origin, as it indicates a high
content of organic matter. The white network interpreted as sparry calcite
cement permits the recognition of the pelletal character of the sample.
This microfacies is a mud-supported bioclastic wackestone in which
the fragments consist mainly of crinoid plates, ostracod valves, calcisphere
and unidentified bioclasts (Fig.2i). The bioclasts may cover 20 to 30 percent
of the slide's surface area. None of these components show any sign of
abrasion. Interstitial spaces are filled with fine-grained detrital quartz and iron
oxide pigments with very few small bioclastic materials.
c
a
b
c
c
q
by
e
d
c
b
c
b
e
Fe
f
o
g
p
h
i
c
Fig. (2) Different types of microfacies can be observed in the YegyanzinWabya area (scale bar = 200µm)
161
Results
The formation of carbonates was controlled by changes in salinity and
alkalinity. Salinity changes are reflected by the composition of the ostracod
fauna. The favourite fossils used in paleosalinity interpretation are ostracods
because these organisms occur in continental, estuarine, marine and
hypersaline waters, because their low-Mg calcite valves are relatively resistant
to diagenetic changes influencing the geochemical data (Flugel, 2004). The
geochemical data are based on four sections from Linwe-Pegin area and three
sections from Yegyanzin-Wabya area.
The major element compositions of 34 representative limestone
samples from Linwe-Pegin area and Yegyanzin-Wabya area were selected for
analyses (Table 3). The Ca content varies from 16.57 to 52.98 wt% with an
average of 34.775 wt% in Linwe-Pegin area whereas it varies from 34.29 to
53.23 wt% with an average of 43.76 wt% in Yegyanzin-Wabya area. It shows
negative correlation with Fe, Mg, Si and Zr contents whereas positive
correlation exists with Sr, Mn and Na contents. It is the indication of
argillaceous input by the elements of Si, Al, K and Fe.
Table (3) Major element distribution in limestones of Yegyanzin-Wabya area
Sample
No
Ca
Si
Fe
Al
K
Mg
Ti
Mn
Sr
Zr
Na
S
Loss
Total
S.1
53.23
1.54
0.55
0.67
1.02
0.91
-
-
0.04
-
-
0.04
-
58
B.12
34.31
7.24
3.72
4.60
3.46
0.57
0.63
0.07
0.03
0.04
3.19
-
0.14
57.86
B.14
-
25.62
10.36
8.78
7.50
1.58
0.93
0.06
0.01
0.09
2.92
-
0.15
57.85
B.21
52.49
1.26
1.47
0.73
1.20
0.71
-
0.07
0.06
-
-
-
0.01
57.99
S.9
49.91
3.87
1.39
1.26
1.36
-
-
0.13
0.07
-
-
-
0.01
57.99
S.20
34.29
8.43
5.75
4.41
3.24
1.13
0.54
0.13
0.03
0.04
-
-
0.01
57.99
W.14
54.46
1.18
0.72
0.45
0.82
-
-
0.28
0.06
-
-
0.03
-
58
W.16
51.32
1.73
2.41
1.04
0.87
-
-
0.54
0.04
-
-
0.04
0.01
57.99
W.21
52.46
1.74
1.00
0.90
1.24
0.39
-
0.18
0.05
-
-
0.03
0.01
57.99
W.26
49.57
2.82
2.40
1.41
1.26
-
0.22
0.25
0.04
-
-
0.03
-
58
W.27
43.29
3.41
2.52
1.86
1.51
0.56
0.23
0.82
0.05
0.03
3.61
-
0.11
57.89
W.29
48.08
2.55
1.16
1.33
1.32
0.36
0.18
0.30
0.05
0.03
2.62
-
0.02
57.98
The relatively high Mn content in some stratigraphic levels is likely to
be related to periods of intensive weathering on continental areas and/or to a
larger availability of Mn2+ due to more reducing sea water conditions.
162
Sodium is considered a useful indicator of salinity of depositional and
diagenetic solutions. B.14 is silty limestone and W.27 is fine-grained
limestone.
Discussion
The lowered part of the section of the Linwe-Pegin area is alternately
composed of crinoidal wackestone-packstone, bioclastic wackestonepackstone and crinoids-ostracod wackestone. Lithofacies of this lowered part
are purple phacoidal limestones that are demarcated by two or three horizon of
1-2 cm thick bioturbated surface. Crinoids, cephalopods, bivalves,
brachiopods, and trilobites fragment in purple phacoidal limestones units.
Mainly ostracods, some crinoids, trilobites and brachiopods observed in
limestones with argillaceous seams. The sediments show much mutual
replacement of silica and calcite- multiple stages of varying pH conditions
(Fig. 3).
Fig. (3) Silica-filled crinoids fragments compare with
calcite-filled in the right
The marine transgression reached its maximum by late Silurian time,
and deep water clastic sedimentation became more widespread (Hutchison,
1989). There are two types of transgressions namely slow transgressions and
rapid transgressions. The slow transgression associated with internal cycles of
carbonate successions which do not interrupt the production of carbonates.
The rapid transgressions associated with terminal cycles of carbonate
163
successions which lead to the drowning of carbonate platforms and the change
from carbonate to clastic systems. In this way, purple phacoidal limestone is
overlained by graptolite shale is the indication of the sediment is overlain by
shale and sea-level fluctuations during Silurian time.
The limestones of the Yegyanzin-Wabya area were certainly deposited
in seas of normal salinity in these areas as indicated by wide-spread
occurrence of stenohaline organisms (for example, crinoids). It is of the
utmost importance in the environmental interpretation is that the crinoidal
limestones in not a homogeneous mass, but rather is composed of numerous
alterations of coarse and fine lithologies. The coarse lithology is represented
by crinoidal limestones in the center of the area which grade laterally into
crinoidal calcarenites which in turn are abruptly replaced laterally by
siltstones. Occasional thin tongues of siltstones may extend well inside the
crinoidal body. The fine-grained lithology is represented by pure calcilutites
in the core of the body, grading laterally into siltstones. The crinoidal
limestone layers indicate times of optimum conditions for the development of
crinoids and associated bryozoans and brachiopods. Essentially clastics were
unable to penetrate the environment because of the screening effect of dense
crinoids colonies. This also explains the abruptness of the lateral contacts with
the siltstone facies.
Conclusion
The study area is located at the northwestern and southern parts of the
Pindaya Range, Shan State (south) in topographic map no. 93C/12 and 93D/9.
Five distinct lithofacies and fourteen microfacies in the Linwe-Pegin area and
five distinct lithofacies and fourteen microfacies in the Yegyanzin-Wabya
area are noticed. The purple phacoidal limestones occur at the base and gray
phacoidal to typical nodular limestones occur at the top of the section. Abrupt
shift of fossil in some stratigraphic level indicate the environmental control
during sedimentation of Silurian sediments. Many of the transgressive
surfaces are marked by fossil diversity in measured stratigraphic section.
The crinoidal limestones, phacoidal (nodular) limestones of Linwe
Formation and whitish grey shales with many graptolites of Wabya Formation
are encountered in Yegyanzin-Wabya area. In addition, the nodular limestones
are encountered during Paleozoic (Silurian–Devonian) and Mesozoic (Jurassic
– Cretaceous). This is the indication of global sea-level transgression with
which nodular forming processes are related. Many of the features related to
transgression include the abrupt disappearance of multiple species of
164
graptolites in the shales; cephalopods, trilobites, echinoids, brachiopods,
ostracod etc in the limestones; and the abrupt appearance of several new
species of these groups.
Acknowledgements
This study was based on my PhD (Thesis). I wish heartedly to thank my supervisor
U Myitta, part-time Professor, Department of Geology, University of Yangon, for many of the
ideas presented in this work. I am deeply indebted to my co-supervisor Dr. Zaw Win,
Professor & Head, Geology Department, Sittway University for giving invaluable
suggestions.
References
Adams, A.E., & MacKenzie, W.S., (1998), A Colour Atlas of Carbonate Sediments and Rocks
under the Microscope, Manson Publishing, London, 180p.
Bencini, A. & Turi, A., (1974), Mn distribution in the Mesozoic rocks from Lima valley,
Northern Appennines, Journal of Sedimentary Petrology, v.44(3), p.774782.
Dunham, R.J., (1962), Classification of carbonate rocks according to depositional texture, in
Ham, W.E. (Ed.): Classification of Carbonate Rocks. American Association
of Petroleum Geologists Memoir. 1, p.108-121.
Flugel, E., (2004), Microfacies Analysis of Limestones: analysis, interpretation and
application, New York, Springer-Verlag, Berlin Heidelberg, 976p.
Myint Lwin Thein, (1973), The Lower Paleozoic Stratigraphy of Western Part of the Southern
Shan State, Burma: Geological Society of Malaysia, Bull. 6, p.143-163.
Scholle, P.A. & Ulmer-Scholle, D.S., (2003), A Colour Guide to the Petrography of
Carbonate Rocks, AAPG, Memoir 77, 474p.
Yin Min Htwe, (2011), Sedimentology of the Silurian rocks of the Pindaya and Bawsaing
ranges, Shan State (south), PhD Thesis, University of Yangon
(Unpublished), 162p.
Crop-Land Suitability Analysis in Hinthada District Using a
Multicriteria Evaluation and GIS Approach*
Nay Win Oo
Abstract
Crop-land suitability analysis is a prerequisite to achieve optimum
utilization of the available land resources for sustainable agricultural
production. In Myanmar, agriculture is the mainstay of national economy.
One of the most important and urgent problems in Myanmar is to improve
agricultural land management and cropping patterns to increase the
agricultural production with efficient use of land resources. The aim of this
study is to determine physical land suitability for rice crop using a MultiCriteria Evaluation (MCE) & GIS approach and to compare present land
use vs. potential land use. The aim in integrating Multi-Criteria Evaluation
with Geographical Information Systems (GIS) is to provide more flexible
and more accurate decisions to the decision makers in order to evaluate the
effective factors. The study was carried out in Hinthada District of
Ayeyarwady Region. Relevant bio-physical variables of soil and
topography were considered for suitability analysis. All data were stored in
Arc GIS 10 environment and the factor maps were generated. In this
research overlaid the land use/cover map with the suitability map for rice
production to identify differences and similarities between the present and
potential land use. This research provided information at local level that
could be used by farmers to select cropping patterns and suitability.
Key words: Land suitability, Land use/cover, Multi-Criteria Evaluation
(MCE), GIS, Rice
Introduction
Agricultural resources are considered to be one of the most important
renewable and dynamic natural resources. Comprehensive, reliable and timely
information on agricultural resources is very much necessary for a country
like Myanmar, where agriculture is the mainstay of our national economy.
In Myanmar, as in many developing countries, there is an urgent need
to use land in the most rational and possible way. In this sense, GIS and RS
technology offers a dynamic tool for multidimensional process of land use.
Remote sensing (RS) provides landscape information synoptically,
repetitively and objectively. It is an important source of spatial information
such as land use/land cover, drainage and topography. GIS is a powerful tool
Professor and Head, Department of Geography, Hinthada University
* Best Paper Award Winning Paper in Geography,(2002)
166
for geo-environmental analysis and appraisal of natural resources. It allows
the user to integrate data bases generated from various sources including RS
on a single platform and analyze them efficiently in a spatio-temporal domain.
The suitable areas for agricultural use are determined by an evaluation
of the climate, soil, and topographical environmental components and the
understanding of local bio-physical restraints. In this kind of situation, many
variables are involved and each one should be weighted according to their
relative importance on the optimal growth conditions for crops through MultiCriteria Evaluation (MCE) and GIS.
One of the most useful features of GIS is the ability to overlay
different layers or maps. However, the overlay procedure does not enable one
to take into account that the underlying variables are not equally important
(Janssen and Rietveld, 1990). One approach that can help overcome such
limitations is MCE (Carver, 1991), which has received renewed attention
within the context of GIS-based decision-making (Pereira and Duckstein,
1993). The objective of using MCE models is to find solutions to decisionmaking problems characterized by multiple alternatives, which can be
evaluated by means of decision criteria (Jankowski et al., 2001). The aim of
this research was to delineate the suitable areas for rice crop using the relevant
variables of soil and topographic database through the MCE technique within
a GIS context to improve rice production and examined the distribution of rice
crop derived from Terra/ASTER image (24 February 2003) in relation with its
suitability level in Hinthada District, Ayeyarwady Region.
Study area
The area selected for this study is Hinthada District in Ayeyarwady
Region. It is the northern most districts in Ayeyarwady Region. It extends
between 17°20' N and 18°31' N latitudes and 94°47' E and 95°48' E.
longitudes (Fig. 1). The district is located far away from the administrative
capital of the division and this is one of the major factors for the
backwardness of the district in developmental activities. The district consists
of six townships namely Kyangin, Myanaung, Ingapu, Laymyethna, Hinthada
and Zalun (Fig. 2). Hinthada District is bounded on the north by Padaung
Township, while on the east the Ayeyarwady River serves as a boundary
between Monyo and Shwedaung Townships. On the southeast the boundary is
167
marked between Taikkyi Township (Yangon Division) and on the south
between Danuphyu Township (Maubin District), Kyonpyaw and
Ngathaingyaung Townships (Pathein District). The western boundary follows
the water divide of the Rakhine Yoma (Rakhine Mountain Range) throughout
its whole length. On the other side of the Yoma lies Gwa Township (Thandwe
District).
Physically, the district is composed of eastern flood plain in the east
the central low land in the middle and western spur region in the west. The
western spur region is the eastern part of Rakhine Yoma which is 76 to 760
meters (250 to 2500 feet) high. Apart from the western spur region, the rest
are low-lying areas with an altitude of 15.24 meters (50 feet) above sea level
(Fig. 3). The Ayeyarwady River is the major river in the district. Above the
Nyaungyo, the first distributaries of the Ayeyarwady, Ngawun forward the
southwest into the sea near Pathein. Ngawun river in the south is the well
known as Pathein River. Other streams are Mamya, Kanyin and Nankathu
chaung join the Ngawun in the south. These tributaries take their source on
Rakhine Yoma and flows through the ox-bow lakes in the east-central part of
the district.
Fig. 1 Location of Hinthada District.
Fig. 2 Townships consist in Hinthada
District.
168
Demographic conditions shows Hinthada as a highly inhabited district,
the total population was 1,569,503 persons in 2002, with an average density of
581 persons per square mile. Hinthada Township has the highest density with
1190 persons per square mile. The eastern slope of Rakhine Yoma and the
swampy areas are sparsely populated. The population of the Hinthada District
is 1,709,876 (District Peace and Development Council, 2009).
Fig 3. Relief of Hinthada District.
Soil and topography database
Soil information was obtained from, Ministry of Agriculture,
Myanmar. The digitized polygons of soil mapping units consisted of 7 soil
mapping units linked to an attribute table of quantitative soil properties. We
also used qualitative soil data in absence of quantitative data. Soil parameters,
i.e., soil texture, soil pH, soil nutrient matter were added to the polygon
attribute table using Arc GIS 10 software and thematic maps were developed
169
for each of the parameters. The UTM coordinate system was used to locate
geographic elements on the maps. Slope and land type information were
obtained from Digital Elevation Model (DEM) using GIS software package
Arc GIS 10. The source of DEM was SRTM (Shuttle Radar Topographic
Mission) which was 30m spatial resolution.
Fig. 4 Soil types of Hinthada District.
Image processing
For this research, in order to generate the present land use/land cover
information, the data of Terra/ASTER which has a spatial resolution of 30 m
pixel size, was processed using ArcGIS 10 software.
Survey of Myanmar topographical sheets (UTM No. 1795, 1895) were
used for rectification of satellite data, selection of ground control points,
locating training samples as well as to identify and authenticate the various
features on the satellite image.
170
First unsupervised classification was done using spatial statistics to
classify the image into a predetermined number of classes. Later, a supervised
classification was done using the maximum likelihood algorithm for 3 spectral
bands corresponding to green, red and near infrared (G, R, NIR). Next,
necessary editing was done by ground truth data. The accuracy of the land
use/cover classification was evaluated by obtaining a classification error
matrix. In order to asses the accuracy of the classified images, random
reference samples of verification were selected. The land use/cover classes of
the surrounding area of these points were checked by visual interpretation
using field verification data. The land use/cover classes were considered
according to the dominant crops in cool season because the satellite image
used in this study for land use/cover mapping was acquired on summer
season. The land use/cover classes were i) paddy, ii) mixed crop, iii) dense
forest, iv) sparse forest, v) swamp, vi) water bodies and vii) sand bars.
Assigning weight of factors and Multi Criteria Evaluation (MCE)
The purpose of weighting is to express the importance or preference of
each factor relative to other factor effects on crop yield and growth rate.
Factors established in this phase are not unique, but they are the most relevant.
Expert opinion of crop specialization was very important in this phase. The
following variables as relevant to suitable rice growing areas: soil texture, soil
moisture, soil pH, soil drainage, soil nutrients, slope and land type as well as a
relevant set of criterion.
Suitability levels for each of the factors were defined; these levels
were used as a base to construct the criteria maps (one for each factor). The
suitability levels were: Highly suitable, Moderately suitable, Marginally
suitable, Not suitable based on the structure of FAO land suitability
classification.
The resolution of all the factor maps were not same, therefore, we
converted all the layers with the same output raster cell size in order to make
an effective weighted overlay. Ratings were provided on a seven-point
continuous scale, which ranges from 1 to 7. This method has been tested
theoretically and empirically for a variety of decision making situations,
including spatial decision making and has been incorporated into a GIS based
decision making procedure (Eastman, et al., 1995 and Malczewski, 1999).
Once the composite layers and their weights were obtained, the MCE
procedure within Arc GIS 10 was applied to produce the map of suitable
171
areas. Finally, the suitability map for rice crop was identified by weighted
overlay using spatial analyst tools in ArcGIS 10.
Overlay present land use/cover and the suitability map
The present land use/land cover map and the suitability map for rice
crop were overlaid to identify differences as well as similarities between the
present land use and the potential land use. For rice crop, a cross table
between the map of suitable areas and the land use/land cover map was
obtained. In this way, we obtained useful information concerning the spatial
distribution of different suitability levels, according to Terra/ASTER
information. This phase allowed us to fine-tune our results, because the
resultant layer provided the information about how the rice crop was
distributed across the various land suitability zones.
Results and Discussions
Image processing result
The land use/cover map derived from the Terra/ASTER satellite image
that was obtained from the supervised classification. Land use/cover types,
which were produced from the combination of the multi spectral bands
corresponding to green, red and near infrared (G, R, NIR) which were found
to be appropriate to identify the land use/cover types in the study area. Image
processing, by means of the supervised classification approach and the
maximum likelihood algorithm, ensured that an acceptable percentage of the
classified pixels were correctly classified. According to the current land
use/cover map, the rice cultivated area was 116,054.64 ha.
172
Fig. 5 Land use/cover of Hinthada District
MCE process and overlaying land use/cover and suitability map for rice
crop
The land suitability analysis was carried out as the land use/cover map
derived from the satellite data was overlaid and the extent of each suitability
level per land use/cover class was calculated. According to Figure 6 the
number of hectares available to each suitability class is as follows: highly
suitable 81,315 ha, moderately suitable 101,412 ha, marginally suitable
130,482 ha and not suitable 23,076 ha which represent 24.2%, 30.2%, 38.8%
and 6.8% of land area respectively. The results showed that highly suitable
areas were found mostly in the soil of Meadow and Meadow alluvial soils,
Gley and gley swampy soils and Swampy soils. These highly suitable areas
were characterized by: plain and low land, soil pH level between 5.5 to 8, soil
drainage poorly to imperfectly drained, soil moisture high, slope level (<1%)
173
and texture class clay; these values are in agreement with those considered in
the literature.
Fig. 6 Land suitability for rice of Hinthada District.
To improve the results, the land use/cover map and the suitability map
for rice were overlaid to identify differences and similarities between the
present land use and the potential land use for the rice crop. This was done
because of the identification and accurate description of current and potential
production areas are essential for research and agricultural development
(Corbett, 1996). According to the present land use/cover map (Figure 5), the
area cultivated with rice was 116,054 ha. The analysis revealed that in the
study area, 70.1% (81,315 ha) of total rice crop was in highly suitable areas,
29.9% (34739.6 ha) was in moderately suitable areas.
In this investigation, the evaluation criteria were selected taking into
considering the crop requirements regarding local conditions. In this MCE, the
factors were selected based on agronomic knowledge of local experts and
reviews of existing literature. Such an approach produced valuable
information on the relative importance of the factors under evaluation and
174
could be a useful precedent for future studies of rice and other crops.
Furthermore, one of the main premises of the RS and GIS-based land
suitability analysis is that the method can help minimize and even solve
conflicts among competing interests regarding land use by providing better
data and information to resolve the problems. This investigation also provides
general alternatives for local farmers in the area of agricultural land
management of a particular crop.
Conclusions and Recommendations
In this study, we applied remote sensing (RS) and GIS techniques to
identify suitable areas for rice crop .The results obtained from this study
indicate that the integration of RS-GIS and application of Multi-Criteria
Evaluation could provide a superior database and guide map for decision
makers considering crop substitution in order to achieve better agricultural
production. This approach has been used in some studies in other countries.
However, in Myanmar this approach is a new and original application in
agriculture, because it has not been used to identify suitable areas for rice
crop. The study clearly brought out the spatial distribution of rice crop derived
from Remote Sensing data in conjunction with evaluation of biophysical
variables of soil and topographic information in GIS context is helpful in crop
management options for intensification or diversification.
This investigation is a bio-physical evaluation that provides
information at a local level that could be used by farmers to select their
cropping pattern. Additionally, the results of this study could be useful for
other investigators who could use these results for diverse studies. This study
has been done considering current land use/cover, topography and soil
properties that affected the suitability classification of land use types.
Therefore, it gives primary results. For further study, we propose to select
more number of factors like soil, climate, irrigation facilities and socioeconomic factors which influence the sustainable use of the land.
Acknowledgements
I am greatly indebted to Acting Rector Dr. San Linn of Hinthada University, for his
permission to work on this research. My heartfelt thanks are due to my first, foremost
teachers and my parents.
References
Carver, S.J., (1991) Integrating multi-criteria evaluation with geographical information
systems. International Journal of Geographical Information System 5 (3),
321.339.
175
Corbett, J.D., (1996) Dynamic crop environment classification using interpolated climate
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Environmental Modeling: Progress Research Issues. GIS World Book, Fort
Collins, pp.117–122.
District Peace and Development Council (2009) Hinthada District Gazette.
Eastman, J.R., Jin, W., Kyem, A.K. and Toledano, J., (1995) Raster procedures for multicriteria/multi-objective decisions. Photogrammetric Engineering and
Remote Sensing 61(5), pp. 539.547.
FAO (1985) Guidelines: Land evaluation for irrigated agriculture. FAO soils bulletin 55.
Food and Agriculture Organization of the United Nations, Rome.
Jankowski, P., Andrienko, N., Andrienko, G., (2001) Map-centered exploratory approach to
multiple criteria spatial decisionmaking. International Journal of
Geographical Information Science 15 (2), 101.127.
Janssen, R., Rietveld, P., (1990) Multi-criteria Analysis and GIS: An Application to
Agriculture Land Use in The Netherlands.
Pereira, J. M. C. and Duckstein, L., 1993. A multiple criteria decision-making approach to
GIS based land suitability evaluation. International Journal of
Geographical Information Science 7(5): 407-424.
Geographical analysis on the variation in agricultural
technology diffusion among the farmers near Taungoo
University
Aung Kyaw1, Ye Ye Than2, Moe Moe3, Kay Thi Aung3
Abstract
This paper analyzed the process of agricultural technology SRI (System of
Rice Intensification Method) diffusion from Taungoo University to the
local farmers based on structured interview conducted to 354 farmers living
near Taungoo University. The results reveal that although SRI method
diffused from Taungoo University to farmers based on the economic, social
and infrastructural factors, many farmers could not adopt it in practice for
lack of investment, for not receiving detailed information, varied physical
environment (flooding or hilly for water control), unreliable weather, and
low education level of farmers. However, majority of these difficulties
could be overcome by means of some modifications in SRI method, giving
training for new technology, providing investment for farming and
guarantee for farm produces. Since SRI method uses less farm input and no
chemical fertilizer, it is one of the ways leading to sustainable organic
farming. Thus, this technology should be encouraged by means of searching
more locally suitable SRI methods and providing farmers with necessary
technology and investments.
KeyWords: Technology diffusion, Farmer, System of Rice Intensification
Introduction
Agriculture sector is the backbone of Myanmar economy. It
contributes 32 percent of GDP and 17.5 percent of total export earnings. In
addition, 61.2 percent of the labour force is engaged in agriculture in 2010
(DAP, 2011). Since majority of farmers are living in rural area agriculture
development plays a key role in alleviating poverty of rural farmers. Myanmar
used to be the largest rice exporter in the region. Later, Thailand and Vietnam
took the leading role in rice export. One of the weak points of Myanmar
paddy cultivation is that farmers put too much reliance on traditional
cultivation methods (Maung Maung Htwe, 2011).
Ministry of Agriculture and Irrigation sets out five objectives for
agriculture development. These strategies are (1) development of new
1. Professor, Dr. Department of Geography, Dagon University
2. Lecturer, Dr. Department of Geography, Taungoo University
3. Tutors, Department of Geography, Taungoo University
178
agriculture land, (2) provision of sufficient irrigation water, (3) provision and
support for agricultural mechanization, (4) application of modern agrotechnologies, (5) development and utilization of modern varieties (DAP,
2011). All these strategies aimed to increase paddy production both by means
of expanding agriculture land and increasing yield per acre from existing
lands. Expansion of agriculture land is carried out by means of agriculture
land area expansion and intensification of existing land use (multiple
cropping). Increased yield is aimed to gain by using high yield varieties and
large amount of farm inputs such as fertilizer, and pesticides.
However, world vision on the paddy cultivation is gradually changing
during the last decades. Since the Green Revolution, world paddy yield
increased substantially. However, recent trend reveals downturn in production
(Spielman and Pandya-Lorch, 2009) due to impact of high-input farming
together with mono-cropping, modern varieties, fertilizer and pesticide use.
Thus, post-Green Revolution perspective demands innovative strategies that
are resources conserving and technologically feasible. In this situation, SRI is
considered as a solution for its knowledge-based low-external input
technology, promise higher yields with no deleterious impacts on natural
resource at affordable costs for poor smaller farmers (Noltze, 2011).
SRI method is not a new technology in Myanmar. Some farmers from
Patheingyi Township, Mandalay Region have already practiced modified SRI
method in paddy cultivation since the beginning of present century. However,
this method was not widely adopted due to too much reliance of farmers on
the traditional methods of cultivation (Aung Kyaw, et al, 2007). Under the
newly elected government, Myanmar is gradually shifting its strategy to gain
high yield by systematically using farm inputs. This strategy was mainly
based on the modified SRI method (good agriculture method) and started
nationwide since early 2011 (Maung Maung Htwe, 2011). New agricultural
methods are usually disseminating to farmer throughout the country by
launching large scale demonstration plots and block-wise crop production
zones at the entrance and exist of each township (DAP, 2011). However, it
takes a long time to diffuse a new agricultural technology from its source to
farmers. Thus, for effective and quick diffusion of a new agriculture
technology to the farmer, researches related to the process of technology
diffusion and constraints that exist between awareness and practice become
necessary.
179
This paper emphasized on the above necessity from the case study of
farmers located near Taungoo University. Paddy and matpe cultivations
started in Taungoo University with the objectives of getting opportunities for
low income university staffs since 2009. However, success in matpe
cultivation (highest yield is about 30 baskets per acre) and successful adoption
of SRI method in paddy cultivation (in some cases, yield is more than 120
baskets per acre), university widen its objectives and now is aiming to become
an agriculture technology dissemination center for local farmers. SRI method
was adopted as a pioneer in the farm of Taungoo University in 2010. This is
one year before the nationwide motivation for adoption of good agriculture
method. Conference on the paddy cultivation by using SRI was also hold at
Taungoo University with the participation of regional authority concerns,
academicians from Yezin Agriculture University, Taungoo University and
other Arts and Science Universities, and 5 farmers from each village tract of
the township in December, 2010.
Research Questions
This paper tried to examine the process of SRI technology diffusion
with the following research questions.
(1) What is the situation of currently practicing farming technology?
(2) What is the situation of agricultural technology diffusion from
Taungoo University to farmers living near the university?
(3) What are the major controlling factors for agricultural technology
diffusion?
(4) Do farmers like to adopt new technology? What are the factors that
constrain in adoption of new technology?
180
Study area
Figure (1) Location of study area (12 Villages)
Source: 1:50000 scale UTM Map No. 1896-05
The study area, Taungoo University is located about 4 miles away in
the west of Taungoo City. Newly constructed road that connect Taungoo and
Yangon-Nay Pyi Taw Highway is passing near the university (Fig. 1). It is
located in Nyaung gaing Village of Sin zeik Village Tract, Taungoo
Township, Bago Region. There are 12 villages included in Sin zeik Village
Tract. Farmers from these 12 villages were selected to study the technology
diffusion.
Data and method
To answer the above research questions, structured interviews were
conducted to 354 farmers living 12 villages included in Sin zeik Village Tract
in June 2011. Since there were 409 farmers in these villages the sample cover
about (86.55) percent of study area. Derived data were analyzed by using
Microsoft Excel. Then, Discriminant Analysis was conducted by using SPSS
Version 16, to find out the factors controlling the diffusion of technology to
the farmers.
181
Previous Studies and Theoretical Framework
Diffusion refers to the spread of a phenomenon over space and through
time (Johnston, et. al, 1995). Information diffuses from the source and passing
through the area of individual socioeconomic conditions before accepting and
finally practices (Aung Kyaw, et al, 2009). Thus, the diffusion and adoption
processes of a new agricultural technology could be explained as shown in
Figure (2). The main source of SRI method is Taungoo University. From its
source, information of SRI method diffuses to the nearby villages. Since there
is no distinguished physical barrier between the university and surrounding
villages, distance measure and media (mode) of diffusion could be considered.
Then, when people get the information, they have to decide whether they
should adopt the new technology or not. In that case, existing infrastructure
that facilitate diffusion, and policy that facilitates or constraint the practicing
of derived information are involved. In addition, individual’s socioeconomic
conditions and traditions follow by both individual people and/or the whole
village control the actual practice. The process passing through the farmer’s
internal and external conditions is the most important part in adoption of a
new technology. If majority of information and technology were diffused to
farmers, they know whether it is good or bad to practice. In many cases,
although farmers accept the information as practicable one and the result will
benefit to them, they could not do in practice due the above mentioned
farmer’s internal and external constraints. If farmer decide to adopt or practice
their derived technology, strong information exchange occurs between the
farmer and source of technology both directly and indirectly.
Figure (2) Process of technology diffusion and practices Modified from (Aung
Kyaw, et al, 2009).
182
System of Rice Intensification and Traditional Rice Cultivation Method
Before considering the technology diffusion, it is necessary to
understand the differences between the traditional agriculture practicing in the
region for nearly 4 decades and more advance method (SRI) practicing in
some other regions of the world. The concept of SRI was developed by Fr.
Henri de Laulanié, a French missionary priest in the mid-1980s in Madagascar
(McDonald, et al, 2005). It was originally aimed to enable small-scale farmers
increase rice yields by using less water and seed. SRI is mainly concerned
with the practice of farmer in managing plants, soil, water, and nutrients. It is
a complex agricultural production system, leading to high agroecological and
biological productivity without necessarily increasing external key inputs such
as mineral fertilizer and pesticides, labour or capital (Noltze, et al, 2011).
There are major differences between traditional paddy cultivation
method and SRI method. First, the seed used in SRI should be carefully
selected because only one seedling is used in one plot thus quality of every
seeds used in cultivation are strongly related to yield. Major paddy seed
distributer is Yezin Agricultural University in Myanmar. Newly developed
hybrid high yield seeds are directly distributed to key farmers. Then, second
generation seeds are further distributed to respective regions from those key
farmers. According to interviews it is observed that only second or third
generation seeds are suitable for high yield because mixing of paddy species
could effect on yield by means of variation in harvesting time.
Second point of difference is method of nursery for seedlings. In
traditional method, an acre of paddy cultivation needs to use 3 to 4 baskets of
paddy seed and 0.122 hectare (0.25 acre) of nursery (plowing) for sowing. In
case of SRI method only 0.22 baskets of seed and 0.0037 hectare (0.0092
acre) (soil nursery block) of land is necessary. Thus, SRI method could save
large amount of seed and labor in land preparation. In addition, soil nursery
blocks could be constructed at the nearest location within the farms, thus,
transportation cost of seedling could be greatly reduced.
Third point is nursery period. In traditional method, young seedlings
were transplanted to the field within 25 and 30 days. In case of SRI method,
however, nursery period is only 8 to 10 days. By means of reducing the
nursery period branching rate of paddy plant will increase nearly two times.
Fourth factor is related to the nature of planting. Instead of planting 3
to 5 seedlings in each planting SRI uses only one seeding in each planting. In
183
addition, SRI method uses wider inter-plant and inter-row distances of each
plot. By means of reducing amount of seedling and increasing distance
between plants, SRI method facilitates paddy plant to be able to take nutrients
more freely than traditional method. This point contributes to the well
development of branching rate. It is also observed that the quality of seed
bearing from the branches is better than the one bearing from main stem.
Thus, even the yield rate is equal, the quality of paddy is better in case of SRI
method.
Fifth point is, intermittent flooding of paddy field in SRI method,
instead of continuously flooding in traditional method. Thus, SRI method
could save water compared to traditional method. In addition, dry and wet
alternation of soil promotes better aeration and encourages development of
roots. Subsequently it contributes to the more branching and healthy plants.
Sixth point is related to sustainability of agriculture. In traditional
paddy cultivation method, farm-inputs such as fertilizer and pesticide are
essential. However, SRI method uses plant compost and silts instead of
chemical fertilizer. Thus, this new technology is more environmental friendly
and leading to the organic farming. Incorporation of organic manure into the
soil supports root activities by stimulating growth promoting bacteria (Mishra,
et al, 2007).
In terms of cost, SRI method saves cost of seed, labour (although it is
more expensive in the very first year under traditional environment), for
pulling out and carrying young seedling, and transplanting. However, it is
necessary to train female labourer in transplanting. In case of Taungoo
University, labour requirement of the transplanting an acre of land was 24
workers in the first year. It is nearly double the amount of traditional
cultivation method. In the second year, however, labour requirement could be
reduced up to 10 and can save 1 to 3 labour per acres than traditional method.
Results
In the first section we posted four research questions. The first
research question is “What is the situation of currently practicing farming
technology?” To understand the first question, knowledge about the
generation of cultivating seed, inter plant and row ranges, number of seedling
planted in each plot, nursery period and condition of water control are
considered. Figure (3) shows the source of paddy seed planting in their farm
in last year. More than 80 percent of farmers use the seed having from
184
previous harvest. Only 18 percent purchase from other named places of high
yield. Actually, about 82.7 percent (n=341) do not even know the generation
of paddy seed they are growing.
Figure (3) Source of paddy seed for nursery (n= 341)
Source: Structured interview (June, 2011).
Table (1) describes the frequency distribution of inter-plant and interrow distances currently practicing by farmer in the study area. Majority of
farmers are practicing 6 inches × 6 inches distance.
In addition, farmers plant different number of seedlings in one plot. In
average 4 seedlings is used for one plot. Some farmers even use up to eight
seedlings in one plot (Fig. 4). The reason for using large amount of seedling in
one plot is that farmers could not use large amount of fertilizer and could not
control the water, then, small amount of paddy yield from each plant in the
plot makes total yield higher since there are comparatively many plants in an
acre of paddy.
Table (1) Inter-plant and inter-row ranges of current farming
Length (inches)
Width (inches)
No. of respondent
4
4
1
4
5
3
4
6
4
4
9
1
5
5
7
5
6
7
5
7
1
185
Length (inches)
Width (inches)
No. of respondent
6
6
168
6
7
47
6
8
23
6
9
8
7
7
55
8
8
13
8
10
2
9
9
6
Total
346
Source: Structured Interview (June 2011)
Figure (4) Frequency distribution of number of seedling plant in each plot
Source: Structured Interview (June 2011).
Frequency distribution of nursery period is shows in Figure (5). It is
very clear that all farmers use seedlings that are last for 25 to 31 days. It is
revealing tradition of paddy cultivation in Myanmar.
186
Figure (5) Frequency distribution of nursery period
The last point that needs to be examined in current cultivation is water
control during the growing period. About 88 percent of farmers control water
very well by means of irrigation and pumping out of water. Another (4)
percent and (2) percent of famers control draining out and draining in water
only. About 6 percent of farmers do not control the water during cultivation
period. This situation is highly related to the nature of rainfall and local
topography in the area. Since the study area is located in the flat plain and
early rainfall is not reliable and irrigation the early period and pumping out of
excess water from the paddy field is essential even in the traditional method.
Current situation of paddy and matpe cultivation is shown in Table (2).
Average area of farm land owned by a farmer is about 6.7 acres. Of them,
about 6.3 acres (2.55 hectares) of matpe is grown as second cropping after
paddy. Usage of fertilizer in one acre of paddy is about 1.7 (50 Kg) bags. It is
below the amount of fertilizer need in an acre of paddy land. Some farmers
could not even use fertilizer. However, matpe is relatively more profitable
crop for a farmer. Thus, they use large amount of fertilizers and pesticides.
Paddy yield per acre is 83.2 baskets per acre and it is higher than national
average of (78.14) baskets in 2010. Average matpe yield is about 14 baskets
per acre.
187
Table (2) Some facts about the current situation of agriculture in Taungoo
University
Average farm
size
Acre
Std.
N
Use of fertilizer/
Yield
pesticide (per acre)
Amount
Matpe
6.3
4.2 251 19802 Kyats
Paddy
6.7
4.4 336 1.36 Bags
Std.
n
Basket
Std.
13561
346
13.9
1.5
298
83.2 19.47
n
4.64 351
From the above mentioned tables and figures, the first question of this
paper could be answered as farmers still using traditional method of paddy
cultivation in practice. Average farm size is about 7 acres and yield is
relatively higher although use of chemical fertilizer is limited.
The second question is, “What is the situation of agricultural
technology diffusion from Taungoo University to farmers living near the
University?” To answer this question farmer are asked whether or not they
know the paddy and matpe cultivations of Taungoo University. The responds
from 354 farmers revealed that 263 (74.3 percent) farmers know it. The rest of
the farmers 91 (25.7 percent) do not know. Then, further question emphasized
on whether they know SRI method or not. Chi-squared Test result shows that
“there is significantly difference between the farmers who know the Taungoo
University’s agriculture and those who do not know, in terms of knowing
SRI” (Table 3). It can be interpreted as most of the farmers know SRI through
Taungoo University.
Table (3) Relationship between knowing of Taungoo University’s agriculture
and knowing of SRI
Know SRI
Do not know SRI
Total
Know Tg U’s Agriculture
66
197
263
Do not know Tg U’s
Agriculture
7
84
91
Total
73
281
354
Source: Structured Interview (May, 2011).
Notes: Chi-squared Test Significant at 0.001level.
76
188
Again it is tested that whether farmers actually know the basic
concepts of SRI method or not. The result is shown in Table (4). Except from
“permanent existence of water on the paddy filed could affect the yield” and
“successively using of same seed effect on yield”, farmer have knowledge of
SRI method. Even for these two factors more than 60 percent of the people
have information. In case of other 3 factors more than 90 percent of farmers
have the right information.
Then, further question is asked to farmers to give reasons for “how
each factor effect on yield”. In that case only very small number of farmers
could answer this question (Table 4). Again, their giving reasons are also
considerably different from what scientists assume. In case of successive
growing of same seed, majority of farmers could give right answer. But in
case of permanent existence of water in the paddy field, adverse answers are
given. They said, for example, that with the continuous existence of water,
weed could not thrive and lead to the high yield. This point is also important
in case of SRI, weeding is necessary for every 10 days. Traditional paddy
cultivation method generally do not need much weeding, because permanent
existence of water automatically eliminate weed and large paddy plants also
cover the sun light that encourage growing of weed. Anyhow, it is fair to
conclude that many farmers have SRI knowledge although there are minor
differences among them.
Table (4) SRI knowledge of farmer in study area
SRI related knowledge
Inter-plant and row distance
effect on yield
Number of seedling in each
plot effects on yield
Nursery duration effects on
yield
Successive growing of same
seed reduces yield
Permanent existence of water
effects on yield
Average
Answer
No
Yes
n
Reason
No
reason
6.0
94.0
319
38
262
5.0
95.0
319
21
282
2.7
97.3
338
5
324
35.1
64.9
322
84
125
21.4
78.6
323
122
132
14.0
86.0
324
Source: Structured Interview (May, 2011).
189
The third research question is “What are the major controlling factors
for agricultural technology diffusion?” To answer this questions, discriminate
variables such as economic, social, traditional, using technology and
infrastructure of each farmer, and grouping variables of whether they know
SRI or not and would like to adopt SRI or not are asked to farmers with
structured interviews. Economic variable is represented by paddy and matpe
cultivation acres while age and education level of farmer are considered as
social variable. Traditional aspect is represented by number of seedling
planted in each plot and nursery duration. Existing technology is measured by
knowing of SRI (in case of knowing SRI this variable is omitted) and average
yield of paddy and matpe by each farmer. As infrastructure (spatial aspect),
straight distance and route distance from the source of technology are
considered. By using above variables, discriminant analyses are conducted.
Results for the variable that discriminating know and do not know of
SRI reveals in Table (5). There variables of matpe cultivation area, education
level of farmer, and Euclidean distance became the discriminant variables of
know and do not know of SRI method. Economically more powerful and
more educated farmers living near the source of technology could quickly
receive technology compared to other farmers. Thus, economic, social and
infrastructure variables are important factors in the distribution of new
agriculture technology.
Table (5) Standardized Canonical Discriminant Function Coefficient for
diffusion of SRI method of Taungoo University to it environ
Variables
Std. coefficient
Do not know
Know
Matpe growing acre
0.575
6.144
6.322
Education
0.431
4.158
4.170
-0.768
2.561
2.510
Euclidean distance
Note: Percentage of correctly groups = 69.7%; F in= 3.84, F out= 2.71); Wilka Lumda
Method. n = 320.
The fourth research question is “Do farmers like to adopt new
technology?” Structured interview results revealed that about 45 percent of
farmers are willing to adopt new technology while the rest (55 percent) are not
willing. To understand the main reasons of this difference, economic, social,
traditional, and infrastructure variables used in above discriminant analysis are
190
used again. Of course, grouping variable become whether farmer would like
to adopt new technology or not. The result is shown on Table (6).
Table (6) Standardized Canonical Discriminant Function Coefficient
for adoption of new technology
Variables
Std. Coefficient
Paddy yield
Nursery Duration
Route Distance
Not willing
Willing
0.524
73.282
73.441
-0.503
28.465
28.458
0.744
3.917
3.935
Explanation Percent= 62.3%; (F in= 3.84, out=2.71); Wilka Lumda Method. n = 310.
Paddy yield, currently practicing nursery duration, and straight
distance from the technology centers are the results as discriminating variables
of whether farmer would like to adopt new technology or not. Paddy yield is
directly related with willingness to adopt new technology. On the other hand,
nursery duration that represents current technology of farmer is indirectly
related to the adoption of new technology. Route distance that represents
infrastructure and nearness to the source of information also directly related to
the technology diffusion. This relationship is a contradiction to the point
found in case of SRI method diffusion. Instead of easily adopted by nearby
farmers, farmers located at a far distance from source of technology are
willing to adopt new technology. This is because farmers living very close to
the university are quite familiar with the practice of SRI in Taungoo
University. They saw the different points: using large amount of labour, large
investment in making of soil nursery blocks, controlling of water, larger
transplant cost (in the case of first year), making of too much detail, etc.
Those points are difficult to carry out in the sense of farmers. But in the case
of final paddy production and total cost calculation they are not involved and
well informed, thus, many farmers living near the university think that they
could not able to adopt new technology.
Table (7) Major difficulties of farmers concerned with introducing of new
technology
Factors
Investment
Water control
Difficulties
Frequency Percent
90
23.7
67
17.6
191
Factors
Techniques
Could not do detail
Weather
Labour
Seed
Weed
Soil is infertile
Others
Total
Difficulties
Frequency Percent
66
17.4
35
9.2
29
7.6
20
5.3
16
4.2
14
3.7
12
3.2
31
8.2
380
100
Source: Structured Interviews (June, 2011). Note: Based on multiple choice.
Table (7) supports the above mentioned point. In this table, three
major difficulties that the farmers have to face in adopting new technology are
mentioned. Of course, investment (about 24%) is the first constraint for
farmers in adoption of new technology. Majority of the farmers possess only
small amount of land and rely only on their farm as a sole source of income.
Thus, they have money only enough to invest on their farms. If some failure
should happen due to bad weather conditions, or destroyed by pest or disease
they could not continue farming and have to borrow money from money
lenders. Due to large interest rate they could not return to normal situation
within one or two years. Water control is second factor that stand as constraint
for farmers in adoption of new technology. Since majority of farm lands are
located on the low land, it is usually flooded during the rainy season and
quickly dried up when monsoon is retreated. Thus, even if they want to adopt
new technology it is difficult to practice directly. Some 18 percent reveals that
they are lacking in detailed technology while 9.2 percent give reason for too
detailed nature of new technology. These points are related to two extreme
processes. One process is the weakness of technology dissemination program
and another is heritage system of farmers. Majority of farmers are getting old
(Structured interview revealed as 50 years in average, ranging from 20 and 84
years). Accordingly, they could not work some detail works. About 7.6% of
farmers give reason for unreliable weather. Since Taungoo is located in the
transition of Dry Zone and Lower Myanmar, annual rainfall of 1956 mm (77
inches) is not well distributed during the monsoon. Sometime entry of
monsoon is late and sometime retreat is faster and farmers face with
difficulties. Other minor constraints include availability of good seed, problem
192
of weeding, and infertile of their farm lands. All these minor difficulties
revealing that SRI method could not practices directly and need to make some
modification based on local variation of climate, relief, and soil.
Conclusions and Discussion
This paper analyzed the situation of technology diffusion from
Taungoo University to farmers of its environment by using data collected
from structured interviews. Results reveal that all farmers are still using
traditional paddy cultivation method although many of them notice about the
SRI methods. Majority of farmers (74.3 percent) know about the SRI methods
practicing in Taungoo University. Chi-squared test result revealed that SRI
method is diffused from Taungoo University to nearby farmers. Further
analysis results show that although majority of farmers know the basic
principles of SRI, they could not give sound reasons for the benefits derived
from it. Thus, the result points that detailed technology dissemination
programs are still necessary in the area.
To understand the controlling factors of technology diffusion,
discriminant analysis is conducted. The result shows that know or do not
know about SRI method is related to the economic (areas of paddy and matpe
cultivation), social (education level), and infrastructure (distance from the
source of technology).
Concerning with adoption of new technology, only less than half (45
percent) of farmers want to adopt new technology. Then, discriminant analysis
is used again to understand the factors that make difference between
willingness and not willingness of adopting new technology. Paddy yield
(positive relation) and nursery duration (negative relation) those represented
current technology of farmers are related to the adoption of new technology.
However, route distance that represents infrastructure and nearness to the
source of information is directly (positive) related to the technology diffusion.
It is due to the point that farmer living near the technology source learn the
initial phase of SRI method that need many labor and detail works compared
to traditional method. Then, since they do not have enough capital they are not
willing to adopt this new technology.
Therefore it can be concluded that although SRI method is diffused to
the farmer from Taungoo University based on the economic, social and
infrastructure factor, many farmers could not actualize in practice for lack of
investment, for not receiving detailed information, different physical
193
environment (flooding or hilly for water control), unreliable weather, and
lower education level of farmers. However, majority of these difficulties could
be overcome by means of some modifications in SRI method itself (it also
resistant to flood and drought), giving training for new technology, providing
investments and guarantees for production. Since SRI method use less farm
input and no chemical fertilizer it is the beginning of sustainable organic
farming. Thus, this technology should be encouraged by means of searching
more locally suitable SRI method and providing farmer with necessary
technology and investments.
References
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between the awareness and practices of rural people in sustainable
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Research Centre, Yangon University 2(1), pp127-147.
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Thuzar Win Shwe, (2007) “Agriculture changes in Ywashe Village,
Patheingyi Township: policy, nature and farmer's response.” Journal of the
Myanmar Academy of Arts and Science 5, pp277-302.
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farmlands of Myanmar.” The New Light of Myanmar 14 and 15 August,
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Meyer, R. (2009): Agricultural technologies for developing countries. Karlsrube.
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Intensification (SRI): a challenge for science, and an opportunity for farmer
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Washington, DC.
Geographical Analysis on Crop Cultivation of Kyaukme
Township
Nyi Nyi Aung
Abstract
Kyaukme Township is located in Northern Shan State in Myanmar in which
agriculture plays important role and crops cultivation is major economic
activity. The cultivation of crops is controlled by physical factors, social
factors, economic factors including demand, market price, accessibility, etc.
Being located in the eastern highland, high land and low land are found.
There is relation between altitude and cropping intensity of the area.
Cultivated area and cropping intensity decrease with altitude. In the study
area, perennial crop is tea and many annual crops such as paddy, maize,
nigar, soya bean and groundnuts are cultivated. Tea cultivated areas occupy
highland area and annual crops are cultivated in low land area. Mixed crops
are also found. Farmers in the area select the crops that pay higher return.
Market demand affects the cultivation of crops in the area. Increase in
production of crops was resulted by using chemical fertilizer, choosing high
yield varieties, etc. crops cultivated areas differ one village tract to another
and cropping intensity varies with altitudes. This paper examines the crops
cultivation of Kyaukme Township from the geographical point of view by
using field observation, informal talks and interviews with farmers.
KeyWords: demand, market price, accessibility, first, second and third
ranking crops, cropping intensity
Introduction
Kyaukme Township is located in Kyaukme District, Northern Shan
State of Myanmar. It has an area of about 3498.7sq kilometers (1350.83 sq
miles). As Kyaukme Township comprises low land and highlands, and not
only perennial crops but also annual crops are grown in the area. More than
half of the people living in the study area are crops cultivators and crops
cultivations are important in the economy of local people. Major perennial
crop is tea and other annual crops are paddy, maize, millet, groundnut,
sesame, sunflower, soya bean, etc.
Research Problem
The physical factors such as location, geology, topography, drainage, climate,
soils and natural vegetation affect the crop cultivation of the area. Therefore,
PhD(Candidate), Department of Geography, University of Yangon
196
research problem of the paper is: Crop cultivated areas differ from one place
to another in Kyaukme Township.
Research Hypothesis
There is relation between altitude and cropping intensity of the area.
Aim
The aim of the research paper is:
-
to study spatial variation of crops cultivated area in Kyaukme
Township
Objectives
-
To find out the factors affecting the crops cultivation
-
To understand difference in crop cultivation of the area
Study Area
State. It is located about 279.7 km (108 mile) away from Mandalay.
It has an area of 3498.7sq kilometers (1350.83 sq miles). It comprises
9 wards and 69 village tracts including 315 villages.
Sources of Data and Methodology
Spatial variation of crop cultivation is studied by using field
observation, interviews and questionnaires with local farmers.
The secondary data were collected from departments concerned and
books. To collect primary data, 18 village tracts were selected from 60 village
tracts and a ward locating in Kyaukme Township by using random sampling
table. Total household of Kyaukme Township was 26394 in 2010 and 1000
household was chosen as sample size to get. To present spatial distribution
pattern of crops, ranking crops and crop combination index are used and
Geographic Information System (GIS) is applied.
The Pearson’s product moment correlation coefficient (r) is applied to
analyze.
197
Physical Background of Kyaukme Township
The physical factors include location, geology, topography, drainage,
climate, soils and natural vegetation. Among them, location, topography,
drainage, climate and soils mainly affect the crop cultivation of the area.
Location
State. It is located between north latitudes 22º10'22" and 22 º 28' 30" and also
between east longitudes 96º 21'15" and 97º 21' 15". It is bounded by Mogoke,
Momaik and Namsan townships and Mingngwet Subtownship on the north,
Hsibaw Township on the east, Yatsout Township on the south, Naungcho
Township on the west.
Topography
Topographic features of the study area support crop cultivation. High
land and low land plains are found in Kyaukme Towship. The areas in the
northern part are higher than those of the south. Tea is cultivated in higher
part such as Pansan Village Tract and other annual crops like paddy, maize,
etc are grown on lowland areas. The area below 1200 meter is 74 percent of
the total area in which annual crops are cultivated and above 1200 meter is 24
percent of the area in which perennial crop especially tea is grown.
Drainage
The rivers and streams are running from north to south in the area and
flow swiftly because of mountainous in character. Dothtawaddy (Namtu
River) is flowing as boundary between Hsibaw and Yetsout townships with
Kyaukme Township. Mogoke and Moemeik townships are divided by
Nanpote Stream. Naungcho Township is bounded by Nanpate Stream. Other
streams are Minkone, Namkaw, Mingtin, Koown, Nantone, Ponewoe, and
Naungkum streams. The streams support annual crop cultivation.
198
Figure 1. Lacation of Kyaukme
Township
Figure 2. Topography and Drainage
of Kyaukme Township
Source: Land Record Department of Kyaukme Township (2010)
Climate
Climate is one of the natural elements which influence natural
vegetation and crop cultivation. The climate has much influence over land
utilization particularly agricultural potential. The maximum temperature of
hottest month is 36 C° (96.8°F) in April and the coldest month is December
having 24 C°( 75.2°F). The total rainfall is 1238 mm (48.7) inches. Rainfall
of Kuyaukme Township is double maximum Fig (3). According to Koppen’s
classification, the area receives subtropical monsoon climate (Cwa).
Soil moisture balance is shown Fig (4). From April to November,
groundwater recharge is prominently found. It means that soil moisture
content is sufficient for cultivation. At that time, farmers cultivate paddy,
maize, millet and sunflower in Kyaukme Township. Between December and
March, soils moisture is not insufficient for crops cultivation. Therefore,
irrigation water is required to cultivate crops in the period.
Soils
Red Brown Forest Soil (Rhodic Ferralsol) is found in Northern part,
and on the well drained hill slope. Mountainous Brown Forest Soil
(Cambisols) are used intensively for production of food and oil crops. A
variety of annual and perennial crops are planted on Cambisols. It is found in
central part and it covers 45 per cent of the township area. Red and yellow
soils (Acrisols) are suitable for production of rain fed and irrigated crops.
Rotation of annual crops with improved pasture maintains the organic matter
199
content. It is found at an ltitude about 1000m (3280.83 inches) above sea
level. It is suitable for diversified agricultures.
Figure 3. Climograph of Kyaukme
Township (2000-2009)
Figure 4. Soil Moisture Balance of
Kyaukme Township
Source: Data obtained from Meteorology and Hydrology Department, Yangon
Demographic Background of Kyaukme Township
Population Growth and Density
In 2003, population increased to 184713 persons with 91301 males
and 93412 females. In 2004, Mingngwet Sub-township was subtracted from
Kyaukme Township and area of Kyaukme Township was redefined.
Therefore, population decreased in 2004. Total population decreased to
149051 persons made up of 78737 males and 70314 females (Table1.). After
that, population increased to 144452 persons composed of 71175 males and
73277 females. It had resulted both from the natural increase and migration. In
2010, the total population of Kyaukme Township was 181074 persons which
constituted 89493 males and 91581 females.
In 2010, the population density of Kyaukme Township was 41.2
persons per square kilometer (107 persons per square mile). Population
density was higher in urban area due to accessibility and job opportunities.
200
Table 1. Population Growth of Kyaukme Township (2001-2010)
Year
Female
Male
Total
2001
91581
89493
181074
2002
91590
89505
181095
2003
93412
91301
184713
2004
70314
78737
149051
2005
72369
70655
143024
2006
71330
69763
141093
2007
71214
65729
136943
2008
71614
69956
141570
2009
72369
70655
143024
2010
73277
71175
144452
Source: Immigration and Population Department, Kyaukme (2010)
Population Distribution
The general pattern of population distribution in Kyaukme Township
is greatly influenced by its relief and transportation routes. Most populated
areas are Urban Wards, Maingtin, Hkomone, Mainglone, Kywegone and
Naungpain with population more than 3000. There are 8 village tracts with
population between 2000 and 3000, 32 village tracts with between 1000 and
2000 and 16 village tracts with less than 1000in 2010. Populated village tracts
are located central part where accessibility is better, land is suitable for
settlement and cultivation of crops. Thus highest concentration of people is
found in urban area beside Mandalay- Lashio road. High land area and less
accessible part are sparsely populated.
Figure 5. Population Density of
Kyaukme Township (2010)
201
Figure 6. Population Distribution of
Source: Immigration and Population Department, Kyaukme (2010)
Gender Ratio
It is the ratio of male to female in population and expresses the number
of men per hundred women. Generally, in rural area, men work heavier work
than female in agricultural activities. The greater number of male in the rural
area work plowing, harvesting, etc. In the study area, male decreased in 2009
because some males go to China and some to Thailand to work.
Table 2. Gender Ratio of Kyaukme Township
Year
Male
Female
2001
98
100
2002
98
100
2003
98
100
2004
98
100
2005
98
100
2006
98
100
2007
98
100
2008
98
100
2009
97
100
2010
97
100
Source: Immigration and Population Department, Kyaukme Township (2010)
202
Labor Force
There were 14445 people in 2009. Sixty seven percent of labours are
engaged in farm work. This shows the importance of the agricultural sector in
the economy of the township. Actually, not all the workforce of present
families is engaged in agriculture. Some migrated to the neighboring countries
for better job opportunity.
Figure 7. Urban and Rural
Population of Kyaukme
Township (2009)
Figure 8. Labour Force of Kyaukme
Township (2009)
Source: Data based from Immigration and Population Department, Kyaukme
(2010)
Economic Background of Kyaukme Township
The major economic activity of Kyaukme Township is Agriculture. In
2000-01, the area of agriculture land was 47877 hectares or 13.6 percent of
the township’s area. In 2009-10, total area of agriculture land was 42881 or
12.25 percent of the township’s area. Four types of agricultural land use such
as le, ya, garden and taungya are found. Most of the factories in the area are
related to agriculture and agro based industries are found. There are 63 rice
mills, 5 oil mills and workshops.
There are two markets: Central Market and Mingalar Market in which
many retail and wholesale shops selling agricultural produces are found. To
send agricultural produces, transportation play important role in the area.
There are 16 motor vehicle lines in which 58 motor vehicles serving in the
area.
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Result and Findings
Crops Cultivation of Kyaukme Township
Major crops cultivated in Kyaukme Township are divided into
perennial and annual crops. On the higher part, perennial crop especially tea is
cultivated.
Perennial Crop
Tea is main perennial crop in the area.
Tea
Tea production depends on climate and labor force. Now, Palaungs use
modern cutting system that increases tea production. Tea leaves are picked
during 8 months from March to November but not from December to
February. Highest tea production is found in from March to April and this leaf
is known as Shwephee. Tea leaves picked from June to October is called
Kharkhan. Tea leaves plucked in winter is called Hninthet. Tea production
varies according to elevation and soils.
In 2000-01, tea cultivated area was 12659 hectares (31281 acre) and
12058 hectares (29796 acre) (95 percent) was harvested.Tea is cultivated in 38
village tracts which are locating northern part of the area because of elevation.
Largest tea cultivated area was Pansan village tracts possessing 929 hectares
in 2010.
In 2000-01, tea cultivated area was 12659 hectares (31281 acre) and
12058 hectares (29796 acre) (95 percent) was harvested.
204
Figure 9.Tea Distribution of Kyaukme Township
Source: Data of Land Records Department, Kyaukme Township
Tea production in 2009-10 was 0.93 metric tons per hectare and it
increased to 1.10 metric tons per hectare due to new branch cutting system.
Tea plant lives over 15 years and tea plants on higher part are difficult to be
picked and tea production decreased in some years. Therefore, over 15 old tea
plants have been cut to increase production and it is very easy to be picked.
This cutting system is demonstrated by Myanmar Agriculture Department.
Tea is cultivated in 38 village tracts which are locating northern part of the
area because of elevation. Largest tea cultivated area was Pansan village
tracts possessing 929 hectares in 2010.
Annual Crops
In the lower part of Kyaukme Township, annual crops are grown. On
le Land, after harvesting paddy, soya-bean or wheat are cultivated. On ya
Land, after harvesting paddy or maize or groundnut, nigar is cultivated.
Paddy, millet, maize, groundnut, sunflower etc are annual crops grown in
Kayukme Township. Annual crops are subdivided into cereal and oil seed
crops.
Cereal crops
Major cereal crop are paddy and maize.
205
Paddy
Paddy is principal cereal crops in Kyaukme Township and takes first
rank in the crop cultivated area. Paddy is grown in all village tracts. Paddy is
chiefly grown on Mainglone, Hekwi, Maingtin, Khayhnin, Sakhanthar,
Hkomone, and Mawmar, Loisaung Village Tracts which are found northern
and southern part of the area (Figure 10.). Mainglone village tract possesses
largest paddy cultivated area because of availability of water from Nankaw
and Nanpate streams.
The major varieties cultivated in the area are 203, 207, khokchin,
khokmonact, kaukhlyin and other paddy varieties are cultivated to small
extent. China hybrid seed call sinshweli paddy was cultivated in some village
tracts. After transplanting, weeding and spraying pesticide were done.
In 2001, paddy cultivated area was 13955 hectares and it increased to
14170 hectares in 2002. It is resulted from increase in paddy cultivation Ya
land. In 2009, area decreased to 13521 hectares because Mingngwet Township
was subtracted from Kyaukme Township. Paddy cultivation in Kyaukme
Township is mostly carried out by human labour although only a few farmers
use tractors. Distribution of chemical fertilizer from agriculture department is
insufficient.
Maize
Maize is one of the cereal crops cultivated in Kyaukme Township. It
occupied the second largest area after paddy and it is cultivated on ya land.
Maize is mainly cultivated in Maingtin, Taunghteik, Namhutaung, Khantke,
Mankyawng, Takhuntaing, Panlawt and Hekwi village tracts.(Fig:11) Maize
are cultivated areas mainly found in the southern and central part especially
along Mandalay-Lashio Road because high accessibility supports the maize
cultivation in the area.
In 2000-01, net sown maize cultivated area was 3401 hectares and it
increased to 6804 hectares due to higher market demand. Maize produced in
Kyaukme Township was sent not only to Mandalay Region but also to China.
Most of the maize produced from Kyaukme Township was bought by
animal’s feed processing factory located in Kyaukme Township.
206
Figure 10. Paddy Cultivated Area of
Kyaukme Township
Figure 11. Maize Cultivated Area of
Kyaukme Township
Source: Data of Land Records Department, Kyaukme Township (2010)
Oil seed crops
Oil seed crops include groundnut, sunflowers and soya bean.
Groundnut ranks first in cultivated area of oil seed crops.
Groundnut
Groundnut is the most important oil seeds crop in Kyaukme Township.
It is grown in 54% of the village tracts in 2009. It is grown in the rainy season
and in cool season. It is cultivated on taungya and ya land. In new taungya
land, groundnut is cultivated as a first crop. It is grown mostly on silted land
and ya land in Kyaukme Township. It requires rainfall 1016 mm (40 inches)
and temperature 22.2˚C (72˚F). Both rainy-season groundnut and winter
groundnut are grown in the area.
Major groundnut cultivated areas were Maingtin, Naungpain,
Sakhanthar, Hkomone, Takhuntaing, Khayhnin and Loisaung village tracts
which are located in low lying southern part of the area (Fig:12).
In 2001, sown acreage of groundnut was 1498 hectare but area
decreased to 1375 hectares in 2007 due to untimely rain. But, net sown area
again increased to 1906 hectares in 2009 and it was resulted from higher price
and market demand. This increase was due to using high yield varieties of
groundnut. Production increased continuously until 2006. But, there is a little
variation in production due to pests and untimely rain in cool season.
207
In 2007 onward, groundnut production again decreased by changing
seeds of groundnut. Farmers changed the variety of groundnut. Although
existing seeds produced high yield, price of the variety was low. Therefore,
farmers change the seeds with another variety which bears less production but
price of it was high.
Figure 12.Groundnut Cultivated Area of Kyaukme Township
Source: Data of Land Records Department, Kyaukme Township (2010)
Other crops are banana, peas, chilies, sugarcane, vegetables, spices,
garlic, potatoes and onion Although medicinal plants, castors, mustard and
buck wheat were not cultivated in 2001, there were many cultivated area of
these crops in 2009.
Ranking crops
Crop ranking indicates the priority given to certain crops in different
localities and relief, soil and the availability of irrigation water as well as other
economic factor. Moreover, it also reveals the suitability of the different parts
of the study area. Tea, a perennial crop, is omitted in presenting ranking crop
due to very small cultivated area.
First Ranking Crops
The spatial distribution of the first ranking crop, on village tract basis,
for the year 2000-2001 and 2009-2010 are presented in Figure 13. and Figure
14.In 2001-02, paddy ranked first in 55 village tracts, maize in 4 village tracts
and millet in 1 village tract. Generally much of the study areas are located on
208
low plains and well suited to paddy cultivation with sufficient rainfall.
Minglone, Mingtin and Khaynin village tracts have much paddy cultivated
area because of nearness to the streams and lower plains than other village
tracts. On ya land, maize is main crop and it is widely grown in southern part
of the Kyaukme Township. Maize was cultivated in Naungpain, Panlot,
Naraikkhant and Hkomone village tracts as first ranking crop. Millet was first
ranking crops in Kunkaw Village Tracts.
In 2009-2010, the number of village tracts cultivating paddy decreased
to 50 and millet in 10 village tracts. In 2009-2010, maize was not grown as
first ranking. Millet cultivated area increased to 10 village tracts.
Table 3. Ranking Crops of Kyaukme Township (2000-2009)
First Ranking Crops
Crops
2000
2009
Village tracts
Second Ranking Crops
Crops
2000
2009
Village tracts
Crops
2000
2009
Village tracts
Paddy
55
50
Paddy
4
9
Groundnut
14
4
Maize
4
0
Maize
23
30
Soya-bean
9
2
Millet
1
10
Millet
3
18
Millet
3
5
Sunflower
27
0
Nigar
1
20
Soya-bean
1
1
Maize
4
1
Nigar
0
2
Non
29
28
Groundnut
1
0
Total
60
60
Total
60
60
Total
60
60
Source: Own calculation, Data Based on Land Record Department
Figure 13. First Ranking Crops of
Kyaukme Township
(2001-02)
209
Figure 14. First Ranking Crops of
Kyaukme Township
(2009-10)
On the basis of village tracts, the crop possessing the second place
changed a lot during the past one decade. In 2001-02, paddy ranked second in
4 village tracts, maize in 23, and sunflower in 27, millet in 3 and soya-bean
and groundnut in 1 village tract and there was no second ranking crop in a
village tract. In 2009-10, paddy took position the second place in 9 village
tracts, maize in 30, millet in 18, nigar in 2 and soya-bean in 1 village tract
(Fig: 15,16). This shows that sunflower lost this land occupancy strength by
replacing millet and maize because of market demand and price of them.
Nigar became second ranking crop in two village tracts.
Third ranking crops
In 2001-02, groundnut ranked third in 14 village tracts, soya-bean in 9,
maize in 4, millet in 3 and nigar in 1 village tract and there was no third
ranking crops in 29 village tracts. On the basis of village tracts, the crop
possessing the third place rank also changed a lot during the past one decade.
210
Figure 15. Second Ranking Crops of
Kyaukme Township
(2001-02)
Figure 16. Second Ranking Crops
of Kyaukme Township
(2009-10)
Figure 17. Third Ranking Crops of Figure 18. Third Ranking Crops
Kyaukme Township
of Kyaukme
(2001-02)
Township (2009-10)
In 2009-10, village tracts cultivating, nigar increased to 20 village
tracts, groundnut decreased to 4 village tracts, millet to 5, soya-bean to 2. Non
cultivated village tracts little changed to 28 village tracts(Fig:17,18).
211
Crops diversification
There are 10 to 30 different crops in an area which only one or several
crops are dominant, i.e., larger in sown acreage. In determining the identity of
critical crop combination, the percentages of total cultivated area occupied by
individual crops are more suitable than other indices like production volume
or value. The measure of relative land occupancy strength is computed for
every crop that holds as much as close to 4 percent of the total cultivated area
of crop land.
The variation of crop diversification also reveals the pattern of crops in
the study area. The degree of crop diversification is determined by many
factors such as soil conditions, characteristics of rainfall, the extent of
irrigation facilities and the location of the cultivated land is the most important
ones. In the study area, crop diversification is largely based on relief and soil.
Calculation of the index of diversification provides a method for generalizing
the relation between the relative strength and the number of crops grown (Yi
Yi Cho, 2010).
Index of Crop Diversification =
Percentage of sown area under x crops
Number of x crops
Actually a number of crops are grown within Kyaumke Township, but
in this analysis the crops that occupy less than 5 percent of the total sown area
of the respective areal unit are excluded. To get the crop diversified index of
an area unit, the percentage of individual crops are summed up and then
divided the number of crops. In this way, indices for each village tracts are
calculated. In this method, the higher the value of index is the lower the
degree of crops diversification.
Table 4. Degree of Crop Diversification with Kyaukme Township
Degree of Diversification
Index Value
2001-02
2009-10
Very high diversification
<10
<10
High diversification
10.01-15.01
10.01-15.01
Little diversification
15.02-20
15.02-20
Very little diversification
>20
>20
Source: Own Calculation, Data Based on Land Records Department
212
Crop diversification of the area changed in the study period. It is
resulted from change in market demand, price, etc. In 2009, the number of
village tracts having high diversification increased from 10 to 23 village tracts
because most village tracts cultivated 4 crops.Village tracts having low
diversification increased from 25 to 34 village tracts because the farmers
living in these village tracts cultivate maize and millet extensively because of
market demand.
Figure 19. Diversification of Crop in
Kyaukme Township
(2001)
Figure 20. Diversification of Crop in
Conclusion
Being part of Shan State, both high land and low land are found in
Kyaukme Township. The topography of the area distinctly shows the effects
on crop cultivation. Tea cultivated area are on the higher part and annual crops
are cultivated on low land.
Existing soils affect the cultivation of crops in the area. Red brown
soils support perennial crop like tea and red and yellow soils annuals crops
such as paddy, wheat, millet, maize, etc.
Shans and Palaungs are traditionally practice agriculture and Shans
mainly cultivate annual crops and Palaungs grow tea. In the area, most of the
agricultural works are done by manual labours. But, some labours especially
male go to China and Thai for the purpose of gaining more income.
Net sown maize cultivated area increased in the study period.
Moreover, production per unit area increased due to cultivation of high yield
213
variety. Farmers extensively cultivate maize to get more income because of
market demand from China.
Similarly, maize cultivated area and production per unit area increase
remarkably due to higher demand and using high yield CP variety. Among
physical factors, effect of topography, drainage and soils are most prominent
and in social factors, population distribution and labour force are determinant
factors.
Acknowledgements
Special thanks are due to Dr. Khin Khin Wai, Professor and Head, Department of
Geography, University of Yangon, for her permission to do this research work. Thanks are
due to Dr. Myint Thida, supervisor, Lecturer, Department of Geography, University of
Yangon, for her guidance and encouragement. I would like to acknowledge my grateful
thanks to my parents for their encouragements and financial supports to conduct the research
work.
References:
Cho Cho San (1998): “Economic study of Kyaukme District, Northern Shan State”,
Unpublished M.A (Thesis) Department of Geography, University of
Mandalay
Hla Way, Thet Lwin and Myo Thant Tyn (2002): Research Methods in Arts and Sciences,
Ministry of Education, Myanmar Academy of Arts and Science.
Singh. J & Dhillon S.S (2004): Agricultural Geography, Tata Mc Graw-Hill Publishing
Company Limited, India.
Yi Yi Cho (2010): A Geographic Assessment on the Agriculture of Dawei Township,
Unpublished, PhD. Dissertation, Department of Geography, University of
Yangon.
Landslide Susceptibility Assessment along OaktwinPaukkhaung Road within Khaboung Reserved Forest Area
Htun Ko
Abstract
The landslide susceptibility assessment is necessary to prevent terrain
degradation. The evaluation of landslide susceptibility requires
understanding of spatial distribution of the factors that control slope
instability. It is known that the behaviour of landslides is difficult to
evaluate because of the various factors that trigger the mass movement. The
Khaboung Reserved Forest Area is one of the significant model teak forests
in Myanmar. Moreover, Oaktwin-Paukkhaung Road which connects the
East and West of Bago Region is also distinct strategy route within Bago
Region. The shallow landslides affect most of the hillslopes in above forest
area and are mainly caused by the agriculture practices especially
replantation. Most of the geographic problems often require the analysis of
many different factors. Additionally, the factors in analysis may not be
equally important. This study deal with a succession of multi-criteria
analyses that outcomes in a series of landslide susceptibility map.
KeyWords: landslide susceptibility, slope
analyses, replantation practice
instability,
multi-criteria
Introduction
Growing concerns on consequences of landslide and alike mass
movements activity has been one of the foci in terms of hazard assessment
policies worldwide. The reason for this is an obvious increase in the rate of
both, the human causalities and material damage induced by some major
landslide occurrences. Seemingly, those occurrences were adhered with the
major recent earthquakes and rain storms and coupled with the human factors
of negligence. But, there are very difficult to predict the landslide occurrences
by how much amount of rainfall received in an interest area. Only rainfall
intensity per hour is a essential factor to express the surface runoff which is
controlling function for landslide occurrences. Other factor like the slope
instability, strength of lithologic structure, slope aspect character, vegetation
cover conditions, and geomorphic phenomena are also considerable functions
for estimating the landslide vulnerability.
Dr., Associate Professor, Department of Geography, Bago University
216
Although the lithologic structures and soil conditions are important
and significant factors to assess the landslide susceptibility and can cause the
slope instability accordance with the impact of rainfall intensity, in the study
area, Khaboung Reserved Forest Area, there have no obvious changed within
above parameters of study area. The red brown forest soils and Pegu Series
lithologic structure are dominated in most of the study area especially along
the Oaktwin-Paukkhaung Road.
Thus, the two landform structures, ridge and valley those have no
vertical slope instability and four slope aspects, North, South, Northeast and
Southwest direction aspects which are become effect for study road existing
nearly east-west alignment will be considered as the major caused factors for
erosional prone areas in study area.
Landslide hazard prediction can be difficult because it is often
impossible to evaluate the spatial and temporal distribution of past events for
large areas, due to gap in the historical record and limited geographic
information which are lack of detailed geologic survey and landform map.
Thus, several method developed and implemented in this field of research
have focused on evaluating landslide susceptibility. The shallow landslide
affect most of the hillslopes in forest areas and are mainly caused by the
agricultural practices especially forest replantation. For this reason, most of
the landslide susceptibility evaluation methods are generally focused on the
study of the factors influencing slope instability. Additionally, the factors in
analysis may not be equally important. Thus, this study deals with a
succession of multi-criteria analysis of geoprocessing that outcome in a series
of landslide susceptibility map.
Study Area
Khaboung Reserved Forest Area, part of the Bago Yoma (mountain
range) is one of the famous teak model forests in Myanmar. It is located in
Oaktwin Township. On the other hand, Oaktwin-Paukkhaung Road is a
strategic road and also a Yoma Passing Road connecting the East and West of
Bago Region. See figure (1). Although this Yoma passing road within a model
forest makes the disappointment for environmental conservation, this also is a
strategic route of economic and social functions for Bago Region. Moreover,
it must have to implement the sustainable management of timber production
in reserved forest areas.
217
As the general geographic setting of Bago Yoma which is generally
ranged from north to south alignment, most of the local ridges are also
stretched north-south alignment. The middle sides of them were sundered to
construct the shortest paths of the road. Thus, the slope instability and steep
sloping were occurred in those areas. Although the mountain range is not
significant high (minimum height is about 100 meter and maximum is nearly
600 meter), it expresses the features providing for much higher ground.
Moreover, rainfall conditions should include to be considering for surface
runoff along the slope aspects. In this research, due to the lack of rainfall
intensity, the rainfall distribution is provided by using interpolation procedure.
Similarly, the soil infiltration rate of the soil variations is a key factor for
landsliding as well as the strengths lithologic structures are also very
important factors. But, if not so, the variations on or near the earth’s surface
such as types of soil, rock types, relief conditions and rainfall distribution are
represented as the controlling factors for surface erosion. See figure (2).
218
The very mountain itself represents a remarkable and exceptional
ambient in terms of environmental phenomena, primarily due to the
dissimilarity to its surroundings and secondly, to its shape and position. As the
matter of fact some of the phenomena are over amplified, so, even though the
mountain is not significant height (the minimum height is about 200 m and
maximum is nearly 800 m) it expresses features reserved for much higher
ground. This addresses climatic diversity, especially regarding the structure
and distribution of rainfall, as well as hydrological features, geomorphological
entities and accordingly, the biodiversity. As such, this mountain has been
studied in many aspects, including the ones related to geotechnical issues.
Figure (2) shows the major controlling factors for landslide vulnerable
function.
219
DEM (Digital Elevation Model) used in this paper is essential by based data
for detecting the earth surface variations is generated from 10 metre interval
contour information of UTM topographic maps with scale of 1:50000 and
streams layers by using the “Topo To Raster Interpolation” procedure. This
procedure specially designed for the creation of hydrologically correct digital
elevation model (DEM). It has been designed to take advantage of the types of
input data commonly available and the known characteristics of elevation
surface. Moreover, the contour information used in this manner is very
appropriate to create the DEM because it can be expressed the manmade
information of elevation that is road construction than Aster DEM.
The topographic features especially landforms of ridges and valley are
derived from DEM accordance with Kanel size 15 and scale factor 0.5 which
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are based on DEM raster information by using ENVI Topographic Modelling.
See figure (3).
One of the most efficient methods to establish the importance of the
factors in landslides susceptibility is the multivariate analysis, like Principal
Component Analysis (PCA). The principal component analysis was used in
order to reduced the redundant information from the variables and transform
them from correlated variables into uncorrelated variables, named principal
component.
For this study when many factors are available an issue of information
redundancy is arising. It is well known that topographic features such as ridge,
valley, pass, plane, and pits, and etc. and slope aspects which have revealed
the eight directional phenomena derived from DEM (Digital Elevation Model)
present a high interdependence, and all of them, often, leads to
underestimation or overestimation of the results. In other words, the results of
PCA can show the erosional priority (or) landform instability in study area
due to considering the two topographic features, ridges and valley, and four
slope aspects (N, S, NE, SW, directions) those are directly related with study
road. Figure (4) represents the selected slope aspects of study area.
Weighted overlaying is a technique for applying a common
measurement scale of values to diverse and dissimilar input to create an
integrated analysis. Mostly geographic problems often require the analysis of
many different factors. This information exists in different raster layers with
different value scales: distance, degree, priority and so on. Additionally, the
factors in our analysis may not be equally important. It may be that the degree
of slope conditions is more important in finding the potential landslide area
than the interval height of elevation. Within a single raster layer, we must
usually prioritize values, a value of 1 represents slopes of 45 to 75 degree, a
value of 2 represents slopes of 35 to 45 degree, and a value of 3 represents
slopes of 30 to 35 degree. If slope is a criteria in finding a potential landslide
area and our evaluation scale is from 1 to 7 by 1, we might give a scale value
of 1 to the input value of 1 (the most suitable area for landsliding with steep
slopes) and a scale value of 2 (the second most suitable slopes). If it was
decided that slopes less than 15 degree would not be considered, all input
values greater than 6 would be assigned a scale of restricted to exclude them.
221
222
Weighted overlay only accepts the integer raster as the input data, such
as land cover or rainfall distribution. Continuous (floating point) raster must
be reclassified as integer before they can use. To get the potential landslide
areas the major analysis tool is weighted overlaying of geoprocessing. In
which, including parameters are erosional prone areas, slope layer, vegetation
223
cover and relief layer of the study area. The five types of landcover condition
are converted to orderly integer layer based on landslide susceptibility
condition. For example, landsliding generally can occur in bare lands than
sparse forest vegetation areas. Thus, the vegetation cover variation was
assigned by one to five integer value.
Vegetation cover is also effect to landsliding. Landsat ETM images
lunch date of May, 2011 use to get the landcover classification. In which
vegetation covers are classified by object based image classification that can
detect the dense high and low vegetation, and sparse high and low vegetation.
See figure (6).
224
Results
This research was conducted in several sequences as methodological
improvements and data availability supplement in one year period. Although
the lithology and soil conditions are the prominent factors to estimate the
landslide susceptibility areas, we had removed above factors in consideration
of final analysis because luck of data available in detailed lithological
structures including bedding planes of underlying rocks and soil infiltration
rate related with rainfall intensity. Landslides occur when the stability of a
slope changes from a stable to an unstable condition. A change in the stability
of a slope can be caused by a number of factors, acting together or alone.
Although the action of gravity is the primary driving force for a landslide to
occur, there are other contributing factors affecting the original slope stability.
Typically, pre-conditional factors build up specific sub-surface conditions that
make the area/slope prone to failure, whereas the actual landslide often
requires a trigger before being released.
225
Figure (7) represents the rating of landslide susceptibility in study area
based on geomorphological characteristics like an erosional prone areas which
is mainly revealed the potential gravitational force conditions. In this figure,
the dark colour spots in small map frame can be seen as the high potential
landslide susceptibility areas than ligh grey colour areas. This highlight dark
colour spots are nearly closed with Oaktwin-Paukkhaung Road at upland areas
of Khaboung Reserved Forest area. The high potential landslide susceptibility
areas those are nearly closed with study road can be found about five places
along the road. To get the well transportation at anytime along the study road
and to manage the surface erosion caused the degradation of model forest
area, these landslide prone areas should be controlled by using appropriate
procedures.
Conclusion
Landslide susceptibility map provides variable information to
administer and scientists. The research points out a suitable display of the
landslide susceptibility, suggesting the zones more or less prone to instability.
However, we use the geomorphological characteristics derived from DEM,
remotely sensed data and very limited survey data in this research. The results
refer to the increase of erosion processes and the change of erosionaccumulation patterns. If we apply the geological structures such as strengths
and detailed strata of rock types and précised soil data based on variations of
rainfall intensity in this research, the results will be more appropriated with
nature.
Since many factors are considered for landslide hazard mapping, GIS
is an appropriate tool because it has functions of collection, storage,
manipulation, display, and analysis of large amounts of spatially referenced
data which can be handled fast and effectively. Remote sensing techniques are
also highly employed for landslide hazard assessment and analysis. In order to
build a more landslide resistant and resilient society, an original GIS-based
decision support system should be developed in order to help emergency
managements better prepare for and respond to landslide disasters. The GISbased landslide monitoring and management system should include the
disaster data processing modules, command and control system and portal
management system. This architecture can provide valuable insights into
landslide early warning, landslide risk and vulnerability analyses, and critical
infrastructure damage assessment.
226
227
References
Booth, A. M, Roering, JJ, Person, JT.: Automated Landslide mapping Using Spectral analysis
and High-resolution Topographic Data: Puget Sound Lowland, Washington,
and Portland Hills, Oregon, Geomorphology 109, pp 132-147, Elsevier
Buengiu, S., Ionus, O., Simulescu, D., Popescu, L.: (2011). River Undercutting and Indused
Landslide Hazard, The Jiu River Valley (Romania) As a Case study,
Geomorphologia Slovaca Bohemica, pp 46-59
Carrara, A., Cardinali, M., Guzzetti, F., (1992). Uncertainty in assessing landslide hazard and
risk. ITC Journal 2, 172–183.
Cruden, D.M., Varnes, D.J., (1996). Landslide types and processes. In: Turner, A.K.,
Guzzetti, F., Cardinali, M., Reichenbach, P., Carrarra, A., (2000). Comparing landslide maps:
a case study in the upper Tiber River basin, central Italy. Environmental
Management 25 (3), 247–263. doi:10.1007/s002679910020.
Guzzetti, F., Carrara, A., Cardinali, M., Reichenbach, P., (1999). Landslide hazard evaluation:
a review of current techniques and their application in a multi-scale study,
Central Italy. Geomorphology 31, 181–216.
Marjanovic, M.: (2009). Landslide Susceptibility Modelling: A Case Study on Fruska Gora
Mountain, Serbia, Geomorphologia Slovaca Bohemica, pp 29-43
Schuster, R.L. (Eds.), Landslides Investigation and Mitigation. National Academy Press,
Washington, DC, pp. 36–75.
Environmental Perception and Environmental Awareness of
Residents in Layshi Township of Naga Land
May Thu Naing
Abstract
The purpose of this paper is to assess the images and perception of rural
people on their environment of study area. Environmental perception and
environmental awareness of rural residents in Layshi Township is studied
by using the results of questionnaires. Three cluster or groups are selected
as sample groups, from Layshi Township of Naga Land. Among these
cluster 331 samples are selected and questionnaires are distributed. GIS
method, Qualitative and quantitative methods are employed to measure the
primary data collected by questionnaires. There are four distinctive
perspectives of environmental perception and images such as physical,
socio-economic, natural hazards and disasters. Perception and images are
closely related to intimate environment of residents of Naga Land. Images
and perception on conservation are related to necessities, conservation
methods, reducing natural disasters, problems related to environmental
deterioration, methods to protect these problems and method to conserve
environmental problems of rural environment.
KeyWords: Environmental
images,
Environmental awareness
Environmental
perception,
Aims and Objectives
Main aims and objectives of these research are to assess the images
and perception of rural residents on their environment, to correlate the
environmental awareness of residents to rural environmental management of
this township and to suggest from shifting cultivation to step farming of the
rural development programs.
Materials and Methodology
To collect primary data for environmental images, questionnaires and
interview methods are applied in this study. Random sampling is used to
collect the primary data. There are three sample governmental staffs, farmers
and others such as sellers, students, monks or religious services. Among these
clusters 331 samples are allocated to distribute questionnaires. GIS,Qualitative
and quantitative methods are employed to measure the primary data collected
by questionnaires. There are 50 questions in questionnaire.
Dr., Assistant Lecturer, Department of Geography, Nationalities Youth Resource
Development Degree College, Mandalay
230
Study Area
Layshi Township is situated in Nagaland of the Sagaing Region,
North-West of Myanmar. It lies between the latitudes of 25 H 00'and 25 H 45'
North and between the longitude of 94 H 00' and 94 H 50' East. The total area of
Layshi Township is about 2738.17 Square Kilometers. It is bounded in the
north by the township of Lahel, in the east by the Kantee and Homalin
Townships, in the south of Tamu Township and in the west by India. There
are 2 sub-townships, 4 wards,18 village tracts or 70 villages on the land area.
There are several small villages under each village tract.
Sagain Region
Union of the Republic of Myanmar
Figure (1) Location of Layshi Township
Physical Environment in Layshi Township
Naga land is located in the northwest of Myanmar.It is bounded in
the north by the township of Patcoin ranges, in the east by the Kachin State,
in the south of Chin State and in the west by India. It includes Lahel, Layshi
and Namyon Township. The main streams are: Nankhar stream from east to
west, Namphok stream from north to south, and Nansalain stream from west
to south.
231
Layshi Township is part of Naga upland .This region is part of the
Naga Ranges which has a rolling topography with an elevation between
1,341.05 m and 1,996.95 m above sea level. Layshi Town lies at 1,354.16 m
above sea level. The highest mountain range is "Saramayti" which rises in
north and which gradually becomes lower towards the south. The highest peak
of Saramayti is layshi Township which is over 3,825.97m.
The drainage water is also obtained from streams and small
springs.The main streams are Matuki, Ywa, Kazoo, Yatagon, Lantha, Haki,
Yadoung, Namkhat, and Nanway stream. The availability of water for Layshi
is related to climate such as temperature and rainfall. Although Layshi
Township lies in the Sub-tropical Zone as it lies above 1,354.16 m to 1,996.34
m above sea level, it receives the Sub-tropical Mountain Climate (Cwb).
November, December, January and February are the months with the lowest
temperature ranging from 4.5 H C to the freezing point. April and May are the
months with the highest average temperature of 21 HC. The annual rainy days
are more than 100 days. There are also variations in the amount of rainfall.
From May to October are the 6 months with the highest rainfall. 98 percent of
the total annual rainfall is being received during these months. December is
the month with the least rainfall and the coldest month.
The annual average rainfall for Layshi is about 100 inches. At present
due to shifting cultivation, deforestation occurs and the decrease in rainfall.
Sometimes a hot dry climate is felt and it is found that the amount of
underground water has decreased. Moreover as forests within the watershed
area are becoming depleted and sediments in the springs and streams.
However after purifying the muddy deposited water, domestic water can be
used. It is also found that the purified drinking water is becoming scarce.
Soil is an important factor for agriculture. The major soil types found
in the study area are mountainous red soil, red-brown forest soil. Mountainous
red soils are found around the area between 914.36 m to 1,523.93 m of
elevation. These soils are covered on the plateau limestone. The topsoil is
mostly composed of humus. As shifting cultivation is carried on after clearing
the hilly land by cutting forests soil erosion occurs. The slopes of the hills are
steep and sheet erosion occurs and as there are many types of sediments
deposited in the stream. Due to the hard bed rocks artesian and tube wells can
not be dug. That is why the natural spring water (water from springs) is being
used for washing clothes and for bathing by the local people.
232
The natural vegetations around the area have been cleared for shifting
cultivation. The consequence of this practice, more erosion of the topsoil on
the slope is intensified. As the region is over 1,353.25 m high, the natural
vegetation is Pine Forest and evergreen forest. But now due to shifting
cultivation and cutting to trees for fire wood, Pine Forests are rarely found and
evergreen forest occupies a narrow area. Taung-Kathit, Laukya, Sakat,
Yamanay, orchid, bamboo are found in evergreen forest.
Human Factors
In 2008, the total population of Layshi Township was 14,649 persons
and in 2012, there was 16,178 persons. The increase of population between
2008 and 2012 was 1,529 persons. The prime factor of the population increase
in this Township is socio-economic conditions. The population density of
Layshi township was 15 persons per square mile. The total rural people is
14,674 persons and the total urban people is 1,504 persons in this Township.
There are 2820 households and 2930 families in this Township. Most of the
images and perception were usually reflected by race and religious
condition. The area is well distributed by various ethnic groups but some of
them are the original groups such as the Naga and the Chins. According to
2012 report, the majority were Naga such as Tangon Naga, Paryar Naga,
Makuyi Narga.
Other minorities ethnic groups included Kachin, Kayin, Bamar,
Rakhine, and Shan. The majority of religious population are Christian in
Layshi Township of Naga Land, the second is Buddhist and Nat worshippers
are less found in the study area. They formed 95 per cent of the total
population. Religion is usually related to ethnic condition. That is why it is
found that there are separate lands before independence period, which are
used as Christian religious lands.
Type of Economic Activities in Layshi Township
The most important economic activity is various types of agriculture
such as dry farming and shifting cultivation on the mountain areas. There is
one main cash crop or paddy which are grown in small acreages in Layshi
Township. Other economic activities include breeders of small-scale animal
husbandry, hunter, door to door seller, manual labours, and sewer for
traditional dress. These all are associated with shifting cultivation.
There are four main types of agriculture in Layshi. These are step
farming, shifting cultivation, dry farming or Ya cultivation and gardens on the
233
village area. These crops are paddy, tea plants, potato, soy-bean, banana,
orange, coffee, rubber, mango. Shifting cultivation is usually found on the
mountain ranges which surround the study area. Villagers cultivate paddy in
some limited land plots on the mountain slopes. Dry farming or Ya cultivation
is found on the gentle slope of the mountain ranges. These dry farms are
mostly practiced in the land plots located on the ranges. Main crops are
sugarcane, corn, sunflower, sesame, and vegetables. Gardens on the study area
are mainly used for tea plants, coffee plants, thitmawe and orange.Gardens are
mainly found near the settlement area.
In order to study the environmental aspects and impacts of agriculture,
32 sample villages were selected in the study area. In the field survey, type of
farming, type of crops and some factors related to inputs of agriculture were
mainly studied. The result showed that environmental consequences would be
related to type and scale of farming. In the case of shifting cultivation, the
farmers produced very small amount of crops and they did not use chemicals
and pesticides. Their farming system was responsible only for the
consequential effect on erosion rather than environmental pollution.
Therefore, only the combination of these different types of agriculture would
impact on erosion and deposition. Shifting cultivation and population growth
produce some pollutants such as air pollution, water pollution and burning
forest.
Land Use Pattern
Land use pattern indirectly influenced on people`s livelihood and their social
environment that in turn related to image and perception of the people living
in the study area. Total land use area of Layshi Township is 2,738.17 Sq Km
in 2012. The land use of Layshi is divided as follows: residential and
institutional land use 102.14 Sq Km, agricultural land use 16.13 Sq Km and
unused land 1,714.23 Sq Km.There is not clear divided industrial land use,
transportational land use, commercial land use, recreational land use.
Land use of Layshi Township in 2012 showed that 33 per cent of total was
forest land, 0.11 per cent of total was residential land and 1 per cent of total
was cultivable land. About 63 per cent of total land use area was waste land.
Among cultivable land 16.13 Sq Km, 52 per cent was shifting cultivation
land, 23 per cent was Ya land, 19 per cent was Taungya land and 6 per cent
was garden land. Agricultural land area is 16.13.Sq Km and there are 2830
families. Thus the ratio of the agricultural area to the amount of the family in
234
Layshi Township is 1:1.4. That means on one acre of land, there is only one
family.
Perceptions and Awareness of Residents in Layshi Township
Environmental perception and environmental awareness of rural
residents in Layshi Township was studied by using qualitative measurements.
Images and perception are gathered from the answers of respondents of
selected sample groups. These sample groups were government staff group,
farmers group and other group (monks, religious leaders, students).
Questionnaires were distributed to 331 samples of these three samples groups
in 32 sample villages.
Awareness on intimate environment of rural residents is analyzed by
studying preferences, notice on physical features such as drainage, flowers,
trees, lakes, creeks, and ponds near living and work places. Therefore, images
and perception are mainly related to work places of respondents.In the
preference pattern of living place, about 2 per cent to 3 per cent of residents
preferred their living place. However, some amount of respondents from
farmer group, government staff group did not prefer their living and work
places. 50 per cent of other groups preferred their living place. The range of
percentage lies between 5 per cent and 11 percent for all respondent groups.
There is a variation in awareness on traditional condition or shifting
cultivation. About 35 per cent of farmers responses that traditional cultivation
is fair. However, 33 per cent of government staffs and 43 per cent of other
group revealed that traditional cultivation is good because they have not other
works. These results showed that the awareness on shifting cultivation is in
moderate condition among all respondents.
Most of the respondents from all sample groups noticed that there are
flowers and trees near their living places. It ranged between 78 per cent and
99 per cent. For respondents from company staff, 99 per cent of them
answered that there are flowers and trees near their living places. These
respondents revealed that there are several good points for environment by
growing flowers and trees. These good points are maintaining and giving
shades, protecting soil erosion and providing beautiful scenes and recreation.
For farmers, high number of respondents, trees can provide maintenance for
weather and climate of Layshi Township. Awareness on lakes and ponds near
living place is very difficult to measure because Layshi Township is rural area
and lakes and water bodies are difficult to see near their living places. Most of
the respondents from all sample groups noticed that there are changes in
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spring, streams and ponds near their living places due to impact of
deforestation in mountainous area and watershed area.
Awareness on physical environment
Aspects of awareness on physical environment include climate and
other physical features because weather condition is very sensitive and people
faces weather conditions everyday for the whole life. Weather events include
temperature and rainfall. For rain, most of respondents from all group
revealed that rainfall is more than previous years. Reason of more rainfall are
normal condition of weather locating in the mountainous zone and less trees in
the region. Most of respondents awared that Layshi Township is located in the
cold region. Therefore, rainfall is more. However, 14 per cent of respondents
did not answer this question because they usually live in their houses, and did
not notice actual rainy condition outside their houses.
For the aspect of temperature, most of the respondents answered that
temperature was higher in recent years than that of previous years. Here again,
70 per cent of government staffs and 65 per cent of farmers reveled that
temperature conditions change significantly. About 48 per cent of other group
pointed out that temperature is higher in recent years. There are several
reasons for increasing temperature. Some respondents said it was normal
condition for region. Other reasons include increasing shifting cultivation,
scattered trees, abnormal climate and deforestation. All respondent groups
revealed that deforestation is one of the reasons for high temperature.
Percentages for this answer are higher among the government staff groups.
Percentages also are high for reasons such as scattered trees, burning forest
and using firewood.
Awareness on physical environment is also measured by images of
residents on whether environment is changed or not. Answer for change of
environment is higher for government staff group and other groups. For
farmer groups percentage on no change is higher than change in environment.
The results of questionnaires showed various aspects of change in physical
environment. These aspects are increased in number of buildings, cleaner
environment, dense population and greening by growing trees. The results
also showed several reasons of changes in physical environment. These
reasons are modernization, dense population, economic development,
reforestation programmes and increased number of immigrants and emigrants.
Among them higher percentage are found for reasons on modernization and
increased immigrants.
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Awareness on socio-economic environment
Awareness on social environment is studied by asking questions
related to change of social environment. In this case, most of the respondents
from all sample groups revealed that there is no significant change in social
environment of Layshi Township. However, up to 37 percent of respondents
said there is a significant change in social condition of Layshi Township. High
percentage on no change in social environment were significantly found for
farmer groups whereas government staff and other, 36 percent and 37 per cent
respectively, answered there is a remarkable change in social environment of
Layshi Township.
There are various aspects of changes in social environment of Layshi
Township. These aspects include immigration, increased population,
unfamiliar dress, and social relations. Among them change of social
environment due to increased population is significant answers from
respondents of all sample groups. Respondents from farmer group emphasized
more on unfamiliar dress and social relations as change of social environment
of Layshi Township.
There are two main reasons in the changes of social environment of
Layshi Township. These are more female than male due to nearness to India,
immigration process. Most of the respondents from questionnaires survey
revealed that there is significant change in cultural environment of Layshi
Township. They accept to change Naga traditional dress for female and male.
Seventy six percent expressed that there is a change in Naga cultural
conditions. Among farmer, about 14 per cent respondents answered that there
is no change in marginal area. There are several aspects for changes in cultural
environment. Main aspects are higher living standards, modernization and
wearing dresses in western styles (India). Most of the people emphasized on
modernization with western living styles. The most significant aspect of
cultural change is reflected in design and styles of dress and clothes. In this
case, most of the respondents (from 85 per cent to 86 per cent) noticed the
change of dress especially for young girls and boys. Nearly 89 per cent of
respondents from government staffs noticed that there is a significant in
designs and styles of dress and clothes. Actually, changes in clothes and dress
styles is strongly related to modernization and near India. Facts can rapidly be
spread through communication facilities and media.
237
The most significant aspect of cultural change is reflected in design
and styles of dress and clothes. In this case, most of the respondents (from 85
per cent to 86 per cent) noticed the change of dress especially for young girls
and boys. Nearly 89 per cent of respondents from government staffs noticed
that there is a significant in designs and styles of dress and clothes. Actually,
changes in clothes and dress styles is strongly related to modernization and
near India. Facts can rapidly be spread through communication facilities and
media.
Among the cultural aspects, changes in house-style are wooden houses
with zinc roof. For this purpose, images on previous house styles and images
on recent house styles were comparatively studied. From this comparison,
awareness on house style was analyzed. In the images on previous house style,
most of the respondents emphasized on bamboo houses and wooden house. In
recent house styles, brick house are rarel for native people.
Images of markets, as stated in the development objectives, income,
employment, public goods, natural resources, environment, stability and
independence of an area are observed in the markets. It is therefore necessary
to understand about the markets and its potential to rural development and
development planning for the future.
Power supply is another aspect for social environment. Images on use
of electricity are related to supply sources. Although major supply is from
government generators, the role of small and private engines is significant in
rural area. The frequencies of uses of these engines are also important for
environment impact. The images of rural residents revealed this situation.
Awareness on environmental problems
Results of questionnaires showed the awareness of rural residents on
several environmental problems. Natural hazards and disasters generally
categorized as fire disasters, flood, earthquake, storm, animals and insects and
diseases. For fire disaster, most of the respondents awared as serious problem.
Twenty seven per cent of the respondents, such as from farmer group,
revealed that fire is very serious problem on burning forest near Taungya
cultivation. But about 33 per cent of respondents from government staffs
revealed that fire is serious environmental problems.
For flood, less than 5 per cent of all respondents from all sample
groups revealed that it is not a serious problem. Three per cent of respondents
from farmer group responded for this question for flood because they are not
238
familiar with flood frequently. In Panset village of Layshi Township, some
farm were closed when there was a flood. Therefore, flood was a problem
near stream for heavy rainy days. Respondents from all groups regarded that
earthquake is a serious environmental problem for Layshi Township.
However, most of farmer emphasized earthquake as a serious natural hazard.
There are higher percentages on very serious and serious category for
problems related to insects and animals. In this case, insects mainly refer to
mouse problem. Therefore, most of the respondents regard insect problems in
Taungya cultivation. However, about 100 per cent of farmer respondents
revealed that insects and animals are serious problems for them but they do
not use pesticide. This is mainly related to their living and working
environment. Their answers reflected conditions of their intimate environment
and experiences. For other respondents, careless waste disposal, Taungya
exten is main factor for deteriorating physical environment. Government staff
revealed that waste disposal, depletion of forest are main actions for
deteriorating environment. Among the actions on deteriorating social
environment, respondents from other group emphasized on careless, bad
drainage and sewage system. Government staff emphasized more on careless
waste disposal. Old men mentioned careless, waste disposal, dress styles and
drunkard are main actions which affect deteriorating social environment of
Layshi Township.
The land holding owned by one family is about (1.14) acres and
agriculture or cultivation of crops is the only occupation in the study area.
Other occupation for the family is not found. The acreages of paddy lands and
"Taungya" lands amounted to 2827 –acres and the average yield of paddy
production was only 53 baskets per acres. as chemical fertilizer are not
applied to the croplands. Generally a family can get only an average of 60
baskets of paddy per acre. It is found that the stored up paddy for the family is
not sufficient. The total population of Layshi Township was 16,178 persons
and the demand for paddy consumption was 194,136 baskets. It is also found
that the stored up paddy in every year is not sufficient for 23 percent of the
population of the township.As for other job opportunities, the villages there
occasionally are occupied in hunting animals. They also search for wood,
bamboos and orchids in the forests but they do not get extra income for
collecting the products from the forest. The total acreage of Ya Lands in the
study area is about (904) acres and the crops grown are sesame, maize,
groundnut, sunflower, mustard for oil, Soya bean and other pulses. Garden
lands occupy (254) acres and oranges are the main crops grown in the study
239
area. Other crops which are grown are tea, coffee, avocado, pear, spice and
condiments.
In Layshi Township, the important systems lacking, in order to
conserve the environment are the systems in the collection of waste and dirty
materials, the system in distributing clear pure water, the system of drawing
dirty water from the drains: the system of collecting and disposing of sewage.
In Layshi Town, in order to get water and to distribute water, construction of
water filtering tanks or reservoirs should be carried on. Moreover the quality
of fresh pure clean water should be maintained. Tax on water should be
collected after getting systematic report or data of water used by the families.
Distribution of water by pump system mechanism, charging of water pipes,
when broken, new pipes should be constructed and installed in new pipes as
the population increases, water should be distributed systematically according
to the rotation system. A geographical point of view, environmental
conservation, awareness of the native of the region has been studied by the
researcher by questioning them through the questionnaires 2 percent of the
respondents from the questionnaires are received from people who moves
from one village to another village.
The study also focused on environmental images and perception on
environmental problems and natural hazards. The results showed several
aspects such as environment images showing on mental maps, images on
natural hazards and disasters, perception on conservation, preferences of
places and images on particular events. Rural residents, showed significant
images on physical features such as mountains and rivers. However, manmade canals are important for rural residents for shifting cultivation. For
natural hazards and disasters, respondents mentioned fire, wind, cyclone,
flood, earthquake, landslide, diseases and environmental pollution. Among
them, respondents emphasized on fire as the most important natural disaster
for rural residents.Images on conservation also showed the importance of
conservation on natural environment. Images and perception on conservation
are related to necessities, conservation methods, reducing natural disasters,
problems related to environmental deterioration, methods to protect these
problems and methods to conserve environmental problems of rural
environment.
240
Fig (2) Natural Dissaster Risk in Myanmar
Fig (3) Natural Dissaster Risk in Myanmar
241
Figure (4) Environmental Awareness and Conservation in Layshi
Discussions and Conclusions
Reasons showed important image of socio-economic environment.
These reasons are for family, for cooking, bad accessibility, necessity and for
re-sale purpose. Most of the respondents knew the causes of the changes in
building styles of markets in villages.In Layshi Township, the statement of the
respondents of the questionnaires regarding their suggestions on various
sectors are given in percentages as follows.
Sixty five percent stated that although the hydro-electric power can be
extracted but as the villagers do not know the techniques and technology of
hydroelectricity. The experts of tapping hydro-electricity should be sent to
train the settlers there 64 percent are the construction of good roads for
transportation, 61 percent of respondents answered for teaches for schools,
medicines for health, doctors, nurses and plans for constructing fly –proof
latrines.
Fifty eight percent revealed that they need electricity to get electric
light in the villages, pure fresh water, drinking water, and permission to
irrigate water with pipes from the nearby springs, 46 percent stated that more
books and journals are needed for the libraries, 45 percent revealed that
Television Media of Myanmar are needed, 36 percent stated that as Nagas are
the least development people, the school children should be trained to become
242
the most outstanding students and government employees and service man
should be sent in order to help in the development of the people of the region.
Thirty two percent answered for loans in order to carry out terracing of
crop land (step farming) for the cultivation of paddy, 30 percent of the
respondents requested government for permission to grant Naga Literature
and Language (Nagaponsaga or Nagamese) to be taught at all the school of
Nagaland, 30 percent asked for permission to build pagodas, 10 percent
answered for the controlling of prices of goods as carried on in India because
the prices of goods are high in Naga Land, 10 percent stated that ethnic
discrimination should be eliminated and upgrading of Naga culture and
civilization should be carried out.
Table (1) Suggestion of Respondents in Layshi Township, 2012
No.
Education
Step
farming
Hydroelectricity
Replantation
Fq
Fq
Fq
%
Fq
%
Particular
%
%
Health
/Doctor,
medicines
Water
supply
Fq
%
Fq
%
1
Government
37
61
23
38
36
59
13
21
31
51
34
56
2
Farmers
74
30
78
31
167
67
34
14
157
63
156
63
3
Other
7
33
5
24
12
57
5
24
5
24
13
24
Total
118
36
106
32
215
65
52
16
193
58
203
61
Table (2) Suggestion of Respondents in Layshi Township, 2012
No.
Particular
Transportation
Fq
1
Government
2
Farmers
3
%
Media
Fq
%
Library
Fq
%
Outside
Education
different
racial
Fq
Fq
%
%
NR
Fq
Total
%
Fq
%
49
80
28
46
30
49
31
51
0
0
6
10
61
100
150
60
111
45
113
45
84
34
2
0.8
10
4
249
100
Other
14
66
10
48
10
47
8
38
0
0
5
34
21
100
Total
213
64
149
45
153
46
123
37
2
1
6
48
331
100
Source: Field observation,2012
243
Figure (5) Suggestion of Residents in Layshi Township, 2012
Source: Table (1) (2) and Field observation, 2012
During the field survey, the need for electricity plays an important
role in Layshi Township the wards of Layshi Town 90 families and villagers
of 26 villages with the help of private-owned generator the electricity is being
distributed and in 20 villagers hydro-electricity with the strength of 3 KVA-10
KVA is being installed and used to get electric light. A system of solar power
energy for electricity with a strength of 1800-Watts is being installed and used
in the villages of Shwephiaye, Ngakyan, Chayar, Lanhlainglhla, Wataw
Village. Hydro- electricity power supply from the power plant station can be
obtained only a few period after its installation but when the electric power
station failed to give electric supply. There are no skilled experts to repair and
mantain the generator or machinery. within the township, there are 188
families in the wards of Layshi town which do not get electricity. The villages
which do not get electricity or electric light are Yawhaw, Modonphi, KukeyYwama, Gikyakhar, Sonmaya, Htawi, Miaungtha, Sainolin, Dainlane- away,
Painnaekone, yadong, Heinkuk, Kyaekaw, Teekon, Htainnaeshan, Shar shane
village and Mopinelok Sub-Townshhip.
The researcher found only the primary schools and post primary
schools. In the natural conservation of environment formal school education
within the school and non-formal school education outside the school are
needed. That is why, in order to upgrade the standard of education from the
244
primary level to a level higher than the level schools in the villages of Kukey,
Mathawyi,Modun Ywama, Wanbae-Ywahoung, Modunphi,Phwelin, YawyN,
sinolin, and Sonmaya. These all schools should be upgraded to the middle
school level and even to the high school level. For non-formal education
outside the school, libraries should be opened and up- to –date journals,
newspapers and books should be kept in the libraries. In order to encourage
children to go to school, full-time teachers (male as well as female) should be
appointed so that they may persuade the children to attend school. This task
for the teachers plays on important role in educating children regarding the
environmental conservation of the Naga Land.
Photo (1) Education Facilities
Photo (2) Non-formal Education
As the transportation is difficult and accessibility is hindered, one
cannot go easily from one village to another. There is less development in the
area, knowledge regarding the upgrading of education, health, socio-economy
and political ideas and knowledge should be imparted to the villagers by the
authority in power. However it is still found that shifting cultivation is still
being carried on, and natural exchange of goods on the barter system is still
carried on. Furthermore knowledge regarding the environmental conservation
has not yet bean known by the people staying in the study area.
245
Photo (11) Gravel Roads accessibility Photo (12) Earth road accessibility
On the eastern side of Layshi Township, lies Htamanthi village of
Homalin Township which is 25 km away from it. The tarred road, car road
and earth road connecting the two townships can be used only in summer but
during winter, these roads cannot be used. Transportaion in rainy season can
be carried on only by motor cycles. On the southern side of Layshi Township,
between Hpapoke and Mopainglut Sub-township, a stone paved (gravel) road
with a length of 3 km was constructed. On the western side between Layshi
and Swamsara a 28 km long military strategic motor cycle road is being
constructed. Local people used foot path on a self- supporting basis in order to
travel by motor cycles. But it is not very successful because the mountains
have steep slopes and ridges. There are many mountain torrents, pedestrians
have to cross the mountain torrents by using non-cabled bridges. Thus good
high quality gravel or stone paved roads should be upgraded. Narrow roads
should be widened so that the roads could become motorable.
Images on transportation are also related to social environment. These
images included types of transport, physical, social and cultural impact of
transport, and good points of rural transportation. Not only socio-economic
conditions but also the knowledge and information of local people improved
due to the road transport infrastructure. Social environment related to health
was also measured by using past experiences such as diseases. Many types of
diseases were mentioned by respondent groups. These diseases included
Malaria, diarrhea, common cold, heart, eye, dysentery, stomach ache and head
ache. Past experiences for these diseases were related to types of sample
groups. Types of diseases these respondents mentioned were related the levels
of these respondents because heart disease, for example, is chronic and
disease of effluents.Respondents mentioned types of diseases, place of
246
treatment, frequency of treatments and images on frequently occurred
diseases. Social environment was also studied by economic environment.
There are several aspects related to work places. These aspects included
ventilation system, and environmental impacts by work place.
In Layshi Township Christians can go to India to study. Religious
Studies at the Technological Bible School can be conducted easily in order to
become posters and teaches of the religious order. As for the Buddhist Monks
who are appointed by the Government Religious Affairs Department, they
served in the mountainous region for two years only and returned to their
monasteries. The development in the religious and social sectors are slow and
weak in Naga Land. That is why, the villages in Layshi Township are still
undeveloped. Major images on social environment included churches and
monasteries. Since Layshi Township is rural area, there are several churches
and some monasteries in this township. Therefore, these churches and
monasteries become important images of rural residents in Layshi Township.
In Layshi Township, there are 67 villages and out of them only 30
villages which carry on a self-help basis in using the water is not sufficient for
the villagers. As pure water is not available for all the villages, water has to be
boiled in order to get a safe drinking water. In 37 villages, during the rainy
season, water is collected by using bamboo pipes which are connected with
one another according to the ideas of the residents.
In summer and winter in order to get water people have to carry water
from the stream which are one or three miles away from their villages. The
wards and villages which meet with difficulties in getting water during
summer and winter are all the wards of Layshi Town, and the villages are
Mathawyi, Yarparmi, Painnaekone, Chaya, Dainekalane-Sanpya, Aungzaya,
Yannwae, Kukey-ywama, Kokainglon, Phonthayat, Jagayan village. The
villages which meet with difficulties in getting water during summer are
Heinkuk, Yadoung, Jilar, wartaw, Soninyan, Mondonphi, Namiyupi,
Dainkalaine- away, Satpyar, Htawyi, Sikeypon, Sharshane Village.
Photo ( 9) Water Supply System
247
Photo (10) Water Pipeline System
The respondents who want to shift and stay in other towns or villages
stated that if they go to the flat plain region they cannot speak Myanmar
language and understand it. Moreover, very few Naga peoples are acquainted
and friendly with the people of other ethnic groups. Although Layshi
Township is only 5.6 km away from the developed country of India there are a
few knowledge of perception and general knowledge as well as understanding
and outlook, regarding Television and telephone connections. It only when
television media and telephone connections are installed adequately, the
socio-economy can be upgraded and the present environment images and
perceptions of Layshi Township can be changed.
Shifting cultivation and irrigated water supply are the two major types
of farming systems simultaneously existing in the mountain areas of the Naga
Land. They have their own advantages, disadvantages and limitations. For
instance, shifting cultivation should be only used in areas with low population
density and relatively high forest coverage. The development of land use
systems in these areas must be determined by the natural, socio-economic and
cultural environment.
Shifting cultivation is carried on once every year by cutting trees
annually. The "Taungya" lands owned by a family are being handed down to
or bequeathed to their own descendents or the people of their own tribes only
which is a limitation in their inheritance law. In changing "Taungya" shifting
cultivation lands to "Terraced Paddy lands or step farming lands it takes a
very long time and it is very hard for the farmer. The cost of manual labours
to charge Taungya land to Terraced paddy land is Kyat 500,000/-per acre in
2012.
248
Layshi Township receives a sub-tropical mountain climate (Cwa). The
use of hydro-electric power supply in order to get electric light in the study
area is still few. It is found that the average annual consumption of fire wood
for fuel for one family was about 7 tons. Within Layshi Township, out of the
virgin forest lands, the annual acreages of forestlands which were cut and
cleared for shifting Taungya cultivation were about 3 Sq km of virgin forest
lands. The total of 5 Sq km of natural virgin forest lands had been cleared
annually. As the rate of population growth had increased virgin lands would
be used more than before and thus by the next 50 years, 30 percent of the
virgin forest area will become deteriorated.
Conservation of environment, reforestation and planting of trees after
felling the trees should and conducted to the native through educating talks. In
carrying out the management of environment, the role of the governing body
of the villages, heads and leaders of the villages are very important. The
problems regarding the ethnic discrimination of the native people of the
region should be lessened and should be eliminated. In order to maintain Law
and order within the township programmers for religious studies and
educators should be taught in the school as well as in other places outside of
the school.
Local people in the study area are engaged in cultivation of crops and
breeding of animals such as water buffalos, oxen, bison, goats, pigs, fish,
chickens. The village of Pansat within Layshi Township reared the largest
number of basin (wild cattle). Fish breeding is carried on in the villages of
Layoun, Phnethayet, Pamset, Sonmara, yadoung, Satpyar and Ngkuan. If fish
breeding is carried on systematically and if fish breeding is taught
systematically to the ignorant native, fish breeding can be successfully carried
on. Chickens and pigs are reared in the compounds of the houses. As disease
spread from animals to man, systematic rearing of animals should be carried
out. If the occupation which produces more family income has increased,
shifting cultivation (Taungya Cultivation) can be changed to other occupation
which produce more income. If other good income producing occupations
appeared, shifting "Taungya" cultivation will no longer be the main
occupation. If shifting cultivation become less forest can be conserved.
Fire is needed to get heat to cook and to warm oneself from the cold
weather. The average annual firewood for fuel needed every year for a family
is about 7112 k.g of fire wood.
249
Photo ( 7 ) Fuel Storage or Firewood Photo ( 8) Fuel Storage or Firewood
The annual cleared forest land for shifting cultivation is 3 Sq km. Once
the shifting cultivation is carried on farming, it was left fallow for about 10 to
15 years. The farmers returned to their first cultivated lands after cultivating
the crops on another new plot of land. During the period the land was used as
grazing land or pasture land or vacant waste land or discarded land.
Photo (3) Shifting Cultivation or Taungya
Photo(4) Terrace or Step farming
or lae
Because of changes in climate, scarcity of limited agricultural lands
which were left as fallow lands from 10 to 15 years, Taungya cultivation or
shifting cultivation should not be carried on. Instead the former Taungya
lands, should be used as Garden lands where garden crops should be grown.
Garden crops such as avocado, oranges citrus fruits (like grape fruit, lemon),
pears and apples, condiments and species can be sold in Indian markets:
plantation crops such as rubber, teak, Pyinkado, eaglewood, tea, and coffee
should be grown. By cultivating these crops, climate changes can be
250
prevented and environmental conservation can be carried on. Moreover the
family income can be increased too.
Photo (5) Garden crops (orange)
Photo (6) Re plantation
Shifting cultivation is the main cause of land degradation. This paper
presents the causes and consequences of shifting cultivation and its potential
land use alternatives. The results of the study show that traditional land
practices, exacerbated by poverty and associated with a lack of technical
knowledge is the main cause for the continuation of unsustainable shifting
cultivation. Low population density, inadequate land for cultivation, low
education levels, policy planning and implementation without local
participation are all factors that influence farmers’ decision to continue
shifting cultivation. Intensive land management through agro forestry is a
promising alternative that can sustainably manage the remaining forest
resources. If adopted, such systems potentially provide good economic
returns, and may significantly reduce rural poverty and protect the border
lines.
251
Fig (6) Suggestion for water Supply System
Layshi Township
Fig(7) Suggestion for Electricity in Layshi in
Township
Fig (8): Suggestion for water Supply System
Fig (9): Suggestion for Education in Layshi
Township
Sources: Field Observation, 2012
252
Acknowledgements
I wish to express my most grateful appreciation to Director-General U Myo Hlaing,
Education and Training Department, Ministry of Border Affairs, Myanmar for field
observations in Naga Land and Principle U Aung Than Myint, Nationalities Youth Resource
Development Degree College, Mandalay for his kindness in giving me permission to do this
research.
I would like to thank my teacher Daw Agnes Klaipo, Retired Professor of
Department of Geography, University of Mandalay, for her critical reading and for correcting
the errors.
I wish to express my most grateful appreciation to my teacher, Dr Maung Maung
Win, Head of Department of Geography, Nationalities Youth Resource Development Degree
College, Mandalay for allowing me to do this research paper.
I am also grateful to all my teachers, friends, officers and staff of Development
committee for their help in field survey in Layshi Township.
Finally, I am indebted to my dear Naga students and my beloved husband, U Khin
Maung Win, for their participation in the collection of data.
References
Administrative Records (2008),Reports, Administrative Department, Layshi Township.
Border and Development Committee Records (2008), Reports, Layshi Township.
Food and Agriculture Organization of the United Nations, FAO (2002), Land-Water Linkages
in Rural watersheds, Proceedings of the electronic workshop. Benjamin
Kiersch. Rome.
Ken-inchi Shibata, Tetuji Yamamoto (1991) About the Distribution of Shifting Cultivation in
Northern Thailand Based on Landsat TM Data, Kokusai Kogyo Co.,
Ltd.Asahigaoka, Hino, Tokyo, Japan.
Rahman, S. A.; Rahman, M. F.; Sunderland, T.C.H, Causes and consequences of shifting
cultivation and its alternative in the hill tracts of eastern Bangladesh,
Bangladesh.
Rahman, S. A.; De Groot, W.T.; Snelder, D.J(2011), Exploring the agroforestry adoption
gap,Financial and socioeconomics of litchi-based agroforestry by
smallholders in Rajshahi (Bangladesh), Netherlands
Sunderlin, W.D.; Huynh Thu Ba, (2010), Poverty alleviation and forests in Vietnam, CIFOR
Bogor, Indonesia.
Cultural Diversification and Integration in Taungoo
4
Yee Yee Than1, Cho Mar Oo2, Ei Ei Khaing3, Myo Ma Ma Wai
Abstract
Taungoo is a multicultural city. Varieties of ethnic groups are living in
Taungoo. The prominent ethnic groups are Bamar, Kayin, Bangladeshis and
Pakistanis, Chinese, Indian and others. They believe in different religion.
This study focuses on cultural diversification and integration in Taungoo.
The main objectives are (1) To know the spatial distribution pattern of
ethnic groups and (2) To find out the factors for the ethnic distribution
pattern in Taungoo. Two research questions are raised for the study. They
are (1) How are ethnic groups diverse in Taungoo? and (2) What are the
driving forces for the concentration in the specific area? The hypotheses are
that, (1) Cultural identity neighbourhood is guarantee for clustering of each
ethnic group and (2) Specific economic activities for livelihood can control
on concentration of same ethnic group on some specific area. The secondary
data such as house No., the name of house owner, ethnic and religion are
obtained from Ward Administrative Office at Taungoo. Primary data are
obtained from structural interview to local people of 11 percent sample for
Kayin houses and 15 percent sample for Bangladeshis and Pakistanis,
Chinese and Indian houses. The key findings for this study is that the
neighbourhood preferences and the specific economic activities for
livelihood control on concentration of same ethnic group in some specific
area.
KeyWords: cultural diversification, cultural integration, ethnic groups
Introduction
Taungoo is located in the north eastern part of Bago Region. It is
located between north latitude 18⁰ 54' 30" and 18⁰ 57' 29" and between east
longitude 96⁰ 24' 40" and 96⁰ 28' 10" (Fig.1). Taungoo urban setting is
composed with 23 wards. Each ward is subdivided into zones. Taungoo is a
multicultural city and different ethnic groups are living in Taungoo. The
prominent ethnic groups are Bamar, Kayin, Bangladeshis and Pakistanis
(Muslim), Chinese, Indian (Hindu) and others. Bamar people are living in all
wards with large proportions. Some ethnic groups like Kayin, Bangladeshis
and Pakistanis, Chinese and Indian people occupy in some zones within
wards. They believe in different religion. Nearly 100 percent of Bamar believe
1. Lecturer, Dr, Department of Geography, Taungoo University
2. Lecturer, Department of Geography, West Yangon University
3. Lecturer, Department of Geography, West Yangon University
4. Lecturer, Department of Geography, Taungoo University
254
in Buddhism. Most of Kayin people believe in Christianity. Bangladeshis and
Pakistanis people believe in Islamic. Indian people believe in Hinduism. All
these varieties of ethnic groups of different religion integrate in study area,
Taungoo.
Figure (1) Location of Taungoo
Research Questions
Two research questions are raised for the study.
1. How are ethnic groups diverse in Taungoo? and
2. What are the driving forces for the concentration of each ethnic
group in the specific area?
Hypothesis
The tentative hypotheses for the research are that,
1. Cultural identity neighbourhood may influence for clustering of
each ethnic group,
2. Specific economic activities for livelihood can control on
concentration of same ethnic group on some specific area.
Objectives
The main objectives are
1. To know the spatial distribution pattern of ethnic groups, and
255
2. To find out the controlling factors on the ethnic distribution pattern
in Taungoo
Data and Methodology
To examine the spatial distribution pattern of ethnic groups in
Taungoo, field survey is mainly conducted during September 2011 to January
2012. Through survey, the facts on ward plan map, house No., owner name,
ethic group and religion of all houses from each ward are collected from Ward
Administrative Office.
Additional interview to dominant ethnic groups except Barma are also
conducted in August 2012. The structured interview is more emphasized on
household size, household head, education, main occupation for family
livelihood, the place of work, settlement duration, perception on
neighbourhood, identity of place and job and the strongest wish to settle in
another place within Taungoo are used for discussing the cultural
diversification and integration in Taungoo. Point data are analyzed by
Average Nearest Neighbour Analysis and Kernel point density distribution
techniques are used for presenting the ethnic distribution pattern.
The sample size for houses of Kayin people is 11% and 15% each for
houses of Muslin, Chinese and Indian people. Sample houses No. for Kayin
people are chosen from Ward No.(19), (20) and (23). Because of totally
87.3% (649 houses) of Kayin people houses are located in these three wards.
Sample houses No. for Bangladeshis and Pakistanis people are chosen from
Ward No.(2), (11), (12), (14), (16), (19), and (23). Totally 82% (649 houses)
of Bangladeshis and Pakistanis people houses are located in these wards.
Sample houses No. for Chinese people are chosen from Ward No.(15) and
(16). Totally 37.87% (141 houses) of Chinese people houses are located in
these two wards. Sample houses No. for Indian people are chosen from Ward
No.(16), (18) and (20). In these three wards 50.8% (73 houses) houses of
Indian people are closely located. In study area, Houses for each ethnic group
are closely distributed in these selected wards.
Ethnic Diversity in Taungoo
Taungoo urban setting is composed with 23 wards with 85335
population and 15000 houses. Different ethnic groups are Bamar, Kayin,
Bangladeshis and Pakistanis, Chinese, Indian and other races such as Kachin,
Paoh, Rakhine, Mon, Shan and Kayah are grouped in others Indigenous
category (Table.1 and Fig.2). It reveals the proportion of total population of
256
each ethnic group. Bamar rank first, then Kayin, Bangladeshis and Pakistanis,
Chinese and Indian follow it. The proportions of main ethnic groups are varies
with ward. In study area, Taungoo, 85.14 % (12769 houses) of total houses
are owned by Bamar and other indigenous people, 6.14% (922 houses) Kayin,
5.28% (792 houses) Bangladeshis and Pakistanis, 2.48% (372 houses) Chinese
and 0.96% (145 houses) Indian. Based on household head or house owner
believes, nearly hundred percent of Bamar people are Buddhist. The 96.73%
Kayin people belief in Christianity. Bangladeshis and Pakistanis people are
Islamic. The 97.3% of Chinese people are Buddhist and 2.7 % Christian.
Indian people believe Hinduism and Buddhism. Those are Taungoo urban
civic culture. It is full with balance mechanism. This study emphasized on the
concentration of distinct ethnic groups such as Kayin, Bangladeshis and
Pakistanis, Chinese and Indian people who are living in their specific area
within Taungoo.
Table ( 1 ) Ethnic Groups of Taungoo (2011)
Sr
No.
1
2
3
4
5
6
7
8
9
10
Ethnics
Bamar
Kayin
Shan
Chin
Rakhine
Mon
Kachine
Kayah
Other Indigenous
Indian, Bangladeshis
and Pakistanis
11 Chinese
Other foreign ethnic
12 groups
Total
Sources:
Total
Population
64994
9014
163
126
79
50
17
12
508
7805
Percent
76.16
10.56
0.19
0.15
0.09
0.06
0.02
0.01
0.60
9.15
1771
2.08
795
85335
0.93
100.00
1. Township Administrative Office, Taungoo
2. Ward Administrative Office, Taungoo
257
Figure (2) Ethnic Groups of Taungoo (2011)
Sources: 1. Township Administrative Office, Taungoo
2. Ward Administrative Office, Taungoo
Spatial Distribution Pattern of Ethnic Groups in Taungoo
Spatial distribution pattern of ethnic groups in Taungoo are displayed
by Kernel point density distribution technique (Fig.3). Probability of 65
percent is used in the analysis. In general, the dominant concentration area of
each ethnic houses are that houses of Kayin people at the eastern part,
Bangladeshis and Pakistanis at the east, southwest and northwest, Chinese
people at the central part of the town and Indian people at the east and central
part of the town.
The region of 65 percent probability distribution for houses of Kayin
people are concentrated at Ward No.(19) with 23.1% and No.(20) with 35.9%
and No.(23) with 28.3%. They are located both side of the Sittaung River and
the eastern part of Taungoo (Fig.4). Churches are located at Ward No.(7), (8),
(20), (22), and (23). Houses of Kayin people scatter around Churches. Some
High Schools are associated with Church. The boundary line between Ward
No.(19) and (20) is continuous and the Sittaung River flows between Ward
No.(19) and (23). So, Ward No.(23) is separately located with them. These
three places account for 87.3% of total houses of Kayin in Toungoo. The
figure is supported by not only with 65 percent probability distribution of
houses of Kayin but also with the location of religious building especially
churches and schools those are the infrastructure for society. These two items
partly control on concentration of Kayin people at these three wards. Ward
258
No.(23) is located along Taungoo-Thandaung Road. And the rolling
topography within Ward No.(20) attract Kayin people to settle in these areas.
The spatial properties like high ground, large compound, free from inundation
and silence attract Kayin people. The main distinct places are both side of
Myogyi Road, Daizu Street, Nuwar Street, Natshinnaung Road, Sanaykon,
Kyauktwinkon and Lawkottera at Ward No.(20), Myopat (circular) Street at
ward No.(19) and Issatu and Kathesu at ward No.(23). In general the
concentration of houses of Kayin is due to good infrastructure like schools,
transport accessibility to Kayin State and the distinct topographic condition of
eastern part of Taungoo. At present, the distribution of houses of Kayin people
in Ward No.(22) is embedded on interlocking ties between same ethnic
community. This relation makes a window to trace and concentrate on a new
location.
Figure (3) Spatial Distribution Pattern of Houses of Kayin, Bangladeshis and
Pakistanis, Chinese and Indian People
Source: Ward Administrative Office
259
Figure (4) Spatial Distribution Pattern of Kayin Group
The area of 65 percent probability distribution for houses of
Bangladeshis and Pakistanis people and distribution of mosques are shown on
(Fig.5).These distribution reveal the relationship between their religious
buildings and houses of Bangladeshis and Pakistanis people. Houses of
Bangladeshis and Pakistanis people are concentrated in 7 wards. Ward No.(2),
(11), (12), (14), (16), (19), and (23) with the percentage share of 11.6%,
18.7%, 12.1%, 14.9%, 5.4%,11.6%, and 7.58% of the whole urban total
houses of Bangladeshis and Pakistanis people.
The main distinct places are Thatyethmaw Street at Ward No.(2),
Dawna Street at Ward No.(19) and both side of Kan Road, U Hmae Street and
Myazigon Pagoda Road. There are 12 mosques in Taungoo. Those are
distributed in Ward No.(2), (11), (12), (16), (17), (18), (19),and (21). Houses
of Bangladeshis and Pakistanis people are concentrated around and near those
religious buildings mosques.
The region of 65% probability distribution for houses of Chinese
people and distribution of Chinese temples are shown on (Fig.6). Houses of
260
Chinese people are mostly distributed in Ward No. (16), (15), and edge of
Ward No. (4), (5), (13), (14) and (17). Chinese temples are distributed at Ward
No. (14), (16) and (17) and then 24.7% of houses of Chinese people are
located in Ward No.(16). The Central Business District (CBD) of Taungoo is
located at Ward No.(16) and (17) which is located near the western part of
Yangon-Mandalay Highway and Railway. Commercial activities are found
there. Chinese people prefer to do trading activities, so they choose to settle in
CBD or near CBD. Within Taungoo urban area, 37.87% of houses of Chinese
people are located at Ward No.(16) and (15). The remaining percentage share
of houses of Chinese people are scattered in urban area.
The region of 65% probability for houses of Indian people and
distribution of Hindu temples are shown in (Fig.6). It is depicted as very small
circular rings along Nuwar Street at Ward No.(20), Kan Road at Ward
No.(16) and Kyarnikan Street at Ward No.(18) with 18.6%, 9.6% and 22%
respectively. There are 15 Hindu temples within Taungoo and 145 Indian
people houses. Hindu temples are distributed at Ward No.(14), (16), (17),
(20), (21) and (22). This condition reveals that, many Indian people were lived
in Taungoo. Most of their main economic activity is animal husbandary. In
Taungoo, urban population increase year after year. So the grazing land
becomes narrow and Indian people are shifted to fringe of Taungoo to get
large grazing land. Therefore Indian people are sparsely distributed within
Taungoo. Above all these condition, it can be concluded that the ethnic groups
are concentrated around its religious building and their religious building
attract the same religion.
261
Figure (5) Spatial Distribution Pattern of Bangladeshis and Pakistanis Group
Figure (6) Spatial Distribution Pattern of Chinese Group
262
Figure (7) Spatial Distribution Pattern of Indian Group
Situation of Respondents
Respondents Age Group
The percentage shares of the age groups of respondents of household
heads are shown in (Table.2).The age of respondents are grouped into under
30, 31to 60 and over 60 years. More than half of respondents of Kayin,
Bangladeshis and Pakistanis and Chinese household heads are concentrated in
group of 31-60 years. The respondents of Indian people are the highest
concentrate in group of age over 60 years and Kayin household heads are
followed it. Younger than 30 years age group is found in Bangladeshis and
Pakistanis and Kayin household heads with 8% and 2.25% respectively.
263
Table (2) Age Group of Respondents of Ethnic Groups
Sr
No.
Bangladeshis
and
Pakistanis
Kayin
Age
N
1 >30
%
N
Chinese
%
N
Indian
%
N
%
2
2.25
8
8.00
0
0.00
0
0.00
2 31-60
58
65.17
71
71.00
17
77.27
3
27.27
3 <60
29
32.58
21
21.00
5
22.73
8
72.73
89 100.00
100
100.00
22
100.00
11
100.00
Total
Source: Structured interview
Household Heads Education
The conditions of household heads education is shown in (Table.3).
Education status is classed into graduate, undergraduate, high school, middle
school, primary school and monastic education level. Graduate level is highest
in Chinese household heads with 54.55%. Kayin, Bangladeshis and Pakistanis
and Indian household heads are concentrated in middle school level with
28.09%, 35% and 27.27%. The age of respondents who older than 60 years
for Kayin and Indian household heads are higher than Bangladeshis and
Pakistanis and Chinese household heads. Therefore, their percent share of
monastic education level is higher than Bangladeshis and Pakistanis and
Chinese.
Table (3) Household Heads Education Status of Ethnic Groups
Sr
No.
Kayin
Education
Status
N
1 Monastic
%
Bangladeshi
s and
Pakistanis
N
%
Chinese
N
%
Indian
N
%
12
13.48
0
0.00
0
0.00
2
18.18
2
Primary
School
15
16.85
32
32.00
2
9.09
2
18.18
3
Middle
School
25
28.09
35
35.00
4
18.18
3
27.27
264
Sr
No.
Kayin
Education
Status
N
4 High
School
%
Bangladeshi
s and
Pakistanis
N
%
Chinese
N
%
Indian
N
%
23
25.84
17
17.00
4
18.18
3
27.27
5 Under
Graduate
4
4.49
3
3.00
0
0.00
0
0.00
6 Graduate
10
11.24
13
13.00
12
54.55
1
9.09
Total
89
100.00
100
100.00
22
100.00
11
100.00
Source: Structure interview
Influencing Factors on Spatial Distribution Pattern of Ethnic Groups in
Taungoo
Neighbourhood Preferences
Taungoo, the multicultural urban area is full with the sense of unity
and diversity. One of the causes of concentration of each ethnic is that their
ancestor had been settled in that space then they take responsibility and
obligation to their generation. The new born still live there.
If someone wants to settle or buy a house, he or she choose the best
and most desirable place based on neighbourhood especially the same ethnic
community which has it own uniqueness. They have a strong preference for
living with their same ethnic community. In general, preferences and
constraints are factors for cultural concentration. Same cultural integration is
provision of opportunities for them because shared of identity based on the
same culture. This cultural common stressed them to form a community and
unity sense of a place. The space and identities of their society encourage trust
on interaction and form of community social cohesion.
In the study area, the reasons of ethnic groups are categorized into
ancestor’s properties, native, occupation, education and others (Table.4). The
proportion on ancestor’s properties item of Bangladeshis and Pakistanis,
Chinese and Indian people are higher than Kayin group. Bangladeshis and
Pakistanis respondents are highly support on native item. These two main
items reveal the condition of generation. Therefore large proportion for the
settlement reasons of Bangladeshis and Pakistanis, Indian, and Chinese people
265
are based on generation with (74.74%), (72.72%), and (63.64%) respectively.
Second priority for Chinese people is occupation item (18.18%). The main
reason for Kayin people is to get the chance of learning education for their
younger generation.
Concerning about their neighbours, 97% of Kayin respondent insist
that their neighbour are Kayin nationality (Table.5). The respondent opinion
for this concentration is mainly due to the same ethnic group (39.5%) and
generation (10.47%). The 77% of Bangladeshis and Pakistanis respondent
insist, their neighbours are Bangladeshis and Pakistanis, this concentration is
mainly due to the same ethnic group (31.17%) and generation (25.97%). The
54.54% of Chinese respondents insist that their neighbours are Chinese due to
relatives (6.25%). The cluster condition is less in Indian. They have
multiethnic neighbours. The respondent’s opinion for the concentration is
mainly caused by the same race and generation.
Table (4) Reasons of Settlement of Ethnic Groups
Reasons for
settlement
Ancestor
properties
Kayin
N
%
Muslim
N
%
Chinese
N
%
Indian
N
%
18
20.22
46
46.00
13
59.09
5
45.45
3
3.37
28
28.00
1
4.55
3
27.27
Occupation
14
15.73
4
4.00
4
18.18
0
0.00
Education
27
30.34
0
0.00
0
0.00
0
0.00
4
4.49
16
16.00
4
18.18
3
27.27
Others
23
25.84
6
6.00
0
0.00
0
0.00
Total
89
100.00
100
100.00
22
100.00
11
100.00
Native
Same ethnic
group
Summing up, the important signals for concentration of the same
ethnic group are primarily caused by the same race environment and secondly
by the generation for Kayin and Bangladeshis and Pakistanis people. The
distinctiveness of same ethnic community has more opportunity and survival
shared by inhabitants at this cultural landscape. Those are ideal scenario of
their neighbours. They do not want to live in non-familiar neighbourhood.
266
They want to live in full with deepest trust, daily interaction and social
cohesion. The religious ties also create the element of trust. They construct
reciprocal network with obligations and responsibilities. Those are coping
ability of each ethnic community. The simplest tie is they tend to associate
with people of the same identity.
N
%
N
%
Kayin
34
39.53
8
9.30
Bangladeshis
and
Pakistanis
24
31.17
20
Chinese
0
0.00
Indian
1
50.00
N
%
N
%
9
10.47
5
5.81
25.97
19
24.68
0
1
6.25
0
0.00
0
0.00
1
50.00
N
Total
Others
Education
Occupation
Generation
Ethnic
groups
Relatives
Same race
Table (5) Reasons for the Concentration of Same Ethnic Groups
%
N
%
N
%
3
3.49
27
31.40
86
100
0.00
0
0.00
14
18.18
77
100
0
0.00
0
0.00
15
93.75
16
100
0
0.00
0
0.00
0
0.00
2
100
Major Economic Activities of Ethnic Groups
Different ethnic groups have different socioeconomic background. In
study area the different ethnic groups dominate in its specific area and this
spatial differentiation on urban area create differences in economic activity
and vice-visa. The economic activity for their livelihood is categorized into 11
types. There are (1) Professional career, (2) Selling, (3) Casal labour, (4)
Farming, gardening and animal husbandry, (5) Food processing and food
shops, (6) Home industry, (7) Repair and rental, (8) Services, (9) Government
and company staff, (10) Retired and (11) Others (Table. 6).
Majority of Kayin people engaged in gardening (33.71%), causal labor
(20.22%) and service activity (13.48%) than other ethnic groups although less
participates in selling activity. Bangladeshis and Pakistanis people are highly
participated in selling activities (62%) and causal labor (14%) follows it.
Chinese and Bangladeshis and Pakistanis people perform in selling (72.73%)
and services activities (18.18%). Indian people engaged in selling activity
with 54.55%.
267
Table (6) Economic Activities of Ethnic Groups
Kayin
Sr
No.
Types
N
%
Bangladeshis
and
Pakistanis
N
%
Chinese
N
%
Indian
N
%
1
Professional
career
4
4.49
0
0.00
0
0.00
0
0.00
2
Selling
8
8.99
62
62.00
16
72.73
6
54.55
3
Causal labour
18
20.22
14
14.00
0
0.00
2
18.18
4
Farming,
gardening,
30
33.71
3
3.00
1
4.55
0
0.00
1
1.12
1
1.00
1
4.55
0
0.00
animal husbandry
5
Food processing
and
food shops
6
Home industry
0
0.00
2
2.00
0
0.00
0
0.00
7
Repair and rental
0
0.00
2
2.00
0
0.00
0
0.00
8
Services
12
13.48
7
7.00
4
18.18
1
9.09
9
Government and
7
7.87
5
5.00
0
0.00
0
0.00
company staff
10
Retired
6
6.74
2
2.00
0
0.00
2
18.18
11
Others
3
3.37
2
2.00
0
0.00
0
0.00
Total
89
100.00
100
100.00
22
100.00
11
100.00
Kayin people participate in professional career with 4.49%. Food
processing activity is participated by Kayin (1.12%), Bangladeshis and
Pakistanis (1%) and Chinese people (4.55%). Share for home industry and
repaired and rental are evenly distributed in Bangladeshis and Pakistanis
people (2% each). Kayin (7.87%) and Bangladeshis and Pakistanis people
(5%) also participate in government and company staff. Retired percentage is
distributed in Kayin (6.74%), Bangladeshis and Pakistanis (2%) and Indian
people (18.18%). Except selling, causal labours, gardening and services, the
remaining items of economic activities are participated by all ethnic groups
with few proportions.
268
More than 50% of Kayin people participate on primary and tertiary
activity. Selling activity is mostly participating by Bangladeshis and
Pakistanis, Chinese and Indian people. This type of activity is pivotal to the
daily substance of their family. The 68.19% of Chinese, (19%) Bangladeshis
and Pakistanis and (36%) Indian participates in tertiary sector. Chinese people
are less practice on causal labor except Kayin and Bangladeshis and
Pakistanis.
Their working places are categorized into at home, CBD, urban area,
Kayin State, Bago Region and others. Bangladeshis and Pakistanis (26%),
Chinese (13.64%) and Indian (18.18%) are working at home. The highest
shares with (68.19%) Chinese respondents are work at CBD then Indian and
Bangladeshis and Pakistanis follow it. More than 30% of respondents of these
four ethnic groups work at urban area. The distinctiveness between these four
ethnic groups is that Kayin people are working at Kayin State (30.34%) and
Bago Region (17.98%). It is because of the main economic activity for Kayin
people are gardening, log cutting and service of elephant (elephant owner).
Most of their gardens are located at 13 miles, Bawgali and Thandaungyi.
Timber field are located at Bago Yoma and other forested area. Therefore
more than 48% of Kayin household heads are working outside Taungoo
(Table. 7).
In study area, most of Chinese and Bangladeshis and Pakistanis
people are especially depend on commercial activity for their survival.
Therefore they choose near the market or CBD area. Primary economic
activity is the favourable and preferable for Kayin people. Their orchard,
garden and rubber yard are situated near the foothill of the eastern margin of
Taungoo Township. Most of the Kayin people who live in urban area are more
prefer to settle closed with their production site. As a result, nearly all of them
settle down in eastern part of Taungoo. For above conditions, the choice of
settlement location is relate to its economic activity.
269
Table (7) Working Place of Ethnic Groups
Kayin
Working
Place
N
Bangladeshis
and
Pakistanis
%
N
%
Chinese
N
%
Indian
N
%
At Home
7
7.87
26
26.00
0
0.00
2
18.18
CBD
1
1.12
25
25.00
15
68.19
3
27.27
Urban
29
32.58
40
40.00
7
31.82
4
36.36
Kayin State
27
30.34
0
0.00
0
0.00
0
0.00
Bago Region
16
17.98
6
6.00
0
0.00
0
0.00
9
10.11
3
3.00
0
0.00
2
18.18
89 100.00
100
100.00
Others
Total
22 100.00
11 100.00
Identity of Places and Types of Occupation
The identity of place and types of occupation for ethnic groups in
Taungoo are shown in (Table.8). In Taungoo, some places and roads have
distinct characteristics with its own identity of living by same ethnic group
associate with their distinct type of occupation. Thatyethmaw Street, Kan
Road, U Hmae Street, Myazigon Pagoda Road and Dawna Street are
dominated by 82% of the total houses of Bangladeshis and Pakistanis people.
The 24.7% of houses of Chinese people are located in Ward No.(16). Nuwar
Street, Kyarnikan Street and the eastern tip of Kan Road within Ward No. (16)
are dominated by houses of Indian people. Myogyi Road, Daizu Street, Nuwar
Street, Natshinnaung Street, Sanaykon, Kyauktwinkon and Lawkoktara are
dominated by 87.3% of total houses of Kayin people.
270
Table (8) Identity of Place and Occupation in Taungoo
Ward/Distinct
places
Kayin (N=89)
N
Ward No. (2)
Thatyethmaw St.
%
Bangladeshis
and Pakistanis
(N=100)
N
%
6
Chinese
(N=22)
N
Indian (N=11)
%
N
%
Others
N
Total
%
N
%
54
5
46
11
100
B=100
%
Ward No. (11)
Kan Rd., U Hmae
St.
14
B=64%
C=21%
O=14%
70
6
30
20
100
Ward No. (12)
Myazigon Pagoda
Rd.
14
B=72%
C=14%
O=14%
78
4
22
18
100
Ward No. (14)
Kan Rd., U Hmae
St.
6
B=33%
O=67%
33
12
67
18
100
Ward No. (15)
Whole
3
B=100
%
33
6
67
9
100
Ward No. (16)
Whole
4
B=100
%
31
9
69
13
100
271
Ward/Distinct
places
Kayin (N=89)
N
%
Bangladeshis
and Pakistanis
(N=100)
N
%
Ward No. (16)
Kan Rd., Marchant
Rd.
%
N
%
Others
N
Total
%
N
%
100
3
100
14
100
100
15
100
100
38
100
Ward No. (19)
Dawna St.
14
B=14%
C=72%
O=14%
15
D=33%
N
Indian (N=11)
10
Ward No. (18)
Kyarnikan Road
Ward No. (19)
Myogyi Road,
Myopat
Chinese
(N=22)
100
H=33%
O=34%
Ward No. (20)
Myogyi Rd., Dezu
Rd.., Sanaygon,
kyauktwinkon,
Lawkoktara,
NuwarSt.
Natshinnaung Rd.
38 C=21%
D=26%
H=32%
O=21%
272
Ward/Distinct
places
Kayin (N=89)
N
Ward No. (20)
Nuwar St.,
Natshinnaung Rd.
Ward No. (23)
Issatu
4 H=75%
%
Bangladeshis
and Pakistanis
(N=100)
N
%
80
Ward No. (23)
Kathesu
N
%
Indian (N=11)
N
%
1
D=25%
26
D=15%
I=8%
O=77%
Chinese
(N=22)
N
Total
%
20
N
%
5
100
30
100
9
100
D=100%
87
2
22
Types of occupation
B –Selling, C-Causal labor, D-Gardening and log cutting, H-Services, I -Government staff, O-Others
Others
7
78
273
The interview result shows that 54% of respondents living in Thatyethmaw
Street. (Ward No.2) accept that people who live in Taungoo knows about the
“Bangladeshis and Pakistanis community live in Thatyethmaw Street. and
100% accept that they all participate in selling activity”. The 70% of
Bangladeshis and Pakistanis respondents who live along Kan Road and U
Hmae Street believe that everybody knows that Bangladeshis and Pakistanis
community live in these places and 64% accept on selling activity. The 78%
of Bangladeshis and Pakistanis respondents who live along Myazigon Pagoda
Road believe that every body knows about their environs as “Bangladeshis
and Pakistanis compound” and 71% accept on selling activity. The proportion
of perception on identity of place and occupation in Ward No.(14) is reduced
to 33% because it is very closed to CBD.
In CBD area, the extent of spatial distinctiveness of single ethnic
group become narrow except Chinese and it is composed with multiethnic
groups. The 35% and 31% of Chinese respondent live in Ward No.(15) and
(16), they also believe that every body knows about that most of residence in
these places are lived by Chinese people and 100% of respondents firmly
accept they are sellers.
For Kathesu in Ward No.(23), and Kyarnikan in Ward No.(18), the
respondent from those places do not know their place identity and occupation
identity. For Dawna Street (Ward No.19), 100% of respondents believes that
urban population know that “Bangladeshis and Pakistanis community live in
Dawna Street” and 100% accept that “they practice in causal labor”.
Exactly 100% of respondents who live along Myogyi Road and
Myopat (circular) Street believe that every ones know about “Kayin
community live in those places” and 33% each accept on their occupation as
gardening and services.
For Daizu Street, Natshinnaung Road, Sanaygon and Lawkottera,
100% of respondents believe that everyone knows “Kayin community
dominate in those places and 26% accept that they practice on gardening, 32%
accept on services and 21% accept on causal labor.
For Issatu in Ward No.(23), 87% of respondents believes that “Kayin
community dominate in this place with multi types of occupation. The 19.8%
of Indian people respondent who live in Nuwar Street and Natshinnaung Road
believe that “the small community, Indian people live along Nuwar Street and
Natshinnaung Road”.
274
Preference Place
Concerning about the strongest wish of respondents to settle a new
place within Taungoo and main reason on that desire is shown in (Table.9 and
10). The proportion for each ethnic group is that Kayin (74%), Bangladeshis
and Pakistanis (69%) and Indian (92%) want to live in present location.
Chinese 73%, of Kayin (10%) and Bangladeshis and Pakistanis (21%) want to
live in CBD. The percentage shares for the types of reasons are calculated
based on the total number of types of the preference place (present location,
CBD). The main reasons are categorized into (1) same race and religion
environment, (2) ancestor properties and (3) relate with occupation. The main
reason for choosing present location which is based on same race and religion
environment is chosen by Kayin (79%) and Bangladeshis and Pakistanis
(29%). Ancestor item is chosen by (70%) of Indian people. Among the choice
of CBD as their strongest wish to settle especially for occupation is Chinese
(44%), (77%) Kayin and (67%) Bangladeshis and Pakistanis.
Table (9) Preference Place to Settle within Taungoo
Bangladeshis
and
Pakistanis
Kayin
Desire
place
N
%
74.00
69
69.00
9
10.00
21
Others
14
16.00
Total
89 100.00
Present
location
CBD
N
%
66
Chinese
N
Indian
%
N
%
0
0.00
10
92.00
21.00
16
73.00
0
0.00
10
10.00
6
27.00
1
19.00
100
100.00
22 100.00
11 100.00
Table (10) Reasons for Preferences
Desire
place
Present
Ethnic
Groups
Kayin
Ancestor
properties
Same
ethnic
group and
religion
N
%
N
%
12.12
52
78.79
8
Occupation
N
%
1
1.52
Others
N
5
Total
%
N
%
7.58
66
100
275
Desire
place
location
Ancestor
properties
Same
ethnic
group and
religion
N
%
N
%
21
30.43
20
28.99
Chinese
3
Indian
7
Ethnic
Groups
Bangladeshis
and
Pakistanis
CBD
N
%
4.35
25
18.75
70.00
Chinese
2
9.52
N
Others
%
Kayin
Bangladeshis
and
Pakistanis
Occupation
3
Total
N
%
36.23
69
100
6
37.50
16
100
4
40.00
10
110
7
77.78
2
22.22
9
100
14
66.67
5
23.81
21
100
7
43.75
Indian
Based on above all conditions, it can be concluded with generation,
cultural identity neighbourhood and specific economic activity are controlled
on concentration of same ethnic group in specific area (Fig.8).
276
Conclusion and Discussion
This paper is studied on the cultural diversification and integration in
Taungoo. It is intended to know the spatial distribution pattern of ethnic
groups and to find out the driving forces for the concentration in some specific
area. The tentative outlines for concentration of ethnic group is that
neighbourhood preferences and the specific economic activities for livelihood
can control on concentration of same ethnic group on some specific area.
The concentration is based not only on physical but also social and
economic activities. The choice of settlement location is also relate to value
(ancestor properties) preferences (same ethnic group and religion
environment, cultural identity neighbourhood) and constraint situation (land
value, affordable, education). Same cultural integration is provision of
opportunities for them because shared of identities (obligations, responsibility,
reciprocal network, ethic) based on same culture. This cultural commons
stress them to form a community and unity sense of a place. The space and
identities of their society encourage trust on interaction and form of
community social cohesion.
The reflection of the structure of economic activity reveals the
clustering of people. The main economic activities of study area can be
categorized into 11 groups and each ethnic group has its own prominent
economy for their survival. There are some striking differences of economic
activity. Kayin people are capable in gardening and services. More than 50%
of Kayin people participate on primary and tertiary activity. The capabilities
of Bangladeshis and Pakistanis, Chinese and Indian are in commercial and
selling activities. This type of activity is pivotal to the daily substance of their
family. The (68.19%) of Chinese, (19%) Bangladeshis and Pakistanis and
(36%) Indian participates in tertiary sector. Chinese people are less practice on
causal labor. Professional carrier is contact by Kayin. Indian people also
concentrate in selling activities. Those are the symbolic markers of the various
work relate to each communities. Due to above situation, distinct ethnic group
are settle on suitable and favourable place which can support convenience on
their social and economic condition.
These variations lead to concentration of ethnic groups on different
space on the surface. This variation in cultural landscape shows the
heterogeneity of entanglements social integration and interaction in Taungoo.
These social integrations and interactions are embedded in specific identities
and that shapes the social dealing of individual in this community and to
277
outside community. This is the evidence on balancing mechanism of urban
civic culture in Taungoo.
References
Amin A, (2002) “Ethnicity and the multiculture city: living with diversity, Environment and
Planning A, volume 34, pages 959-980.
Hanson K T, (2005) “Landscapes of survival and escape: social networking and urban
livelihoods in Ghana”, Environment and Planning A, volume 37, pages
1291-1310.
Report of Township Administration Office Taungoo (2011).
278
Structured interview questions
A. Family Status
1. Ethnic ---------------- Religion---------------------House No.---------------------2. Family size (
), Household head education-------------------------------------
3. Main economic activity for family livelihood------------------------------------4. Starting year of settlement------- Previous living Town/ Township---------Reason to settle in present location--------------------------------------------------Reason to choose present location---------------------------------------------------B. Neighbours
5. Ethnic group of your neighbor------------------------------------------------------6. Opinion for concentration of same ethnic group
Same race
relatives
occupation
others
7. Distinctiveness of your neighbor (1) -------- (2) ------- (3) -------- (4) --------8. Satisfaction on neighbours
strongly satisfied
satisfy
unsatisfied
strongly unsatisfied
Reasons--------------------------------------------------------------------------------C. Distinct cultural activity of neighbour
9. Racial festival (1)------------(2)---------- (3)-----------(4)-----------(5)----------10. Satisfaction for participate on racial festival
strongly satisfied
satisfy
unsatisfied
strongly unsatisfied
11. Identity of place ---------------------- and occupation--------------------------12. Preference place to settle a new ward -------------- road/street---------------Reason--------------------------------------------------------------------------------
A Geographical Analysis of Markets in Thingangyun
Township
Min Min Aye Than1 and May Myat Phone2
Abstract
Theoretically, markets are located in the place where demand (population or
consumer) and supply (seller) meet together. However, in practice above
concept is more complicated due to hierarchical differences in market,
variations and transportation system and different natures of customers.
This paper attempts to find out the factors that control the development of
markets to in Thingangyun Township. The main objectives of this papers
are: (1) to understand the current hierarchical distribution of markets in
Thingangyun Township, (2) to examine the factors that are controlling the
distribution of markets in Thingangyun Township, and (3) to evaluate the
present locations of markets in Thingangyun Township. For the above
objectives, official statistics related to population, markets, etc. are collected
from township administrative office. These statistics are verified by field
observation and recorded on Geographic Information Systems. Then, spatial
analysis is conducted by using ArcGIS Version 10 software. Based on
derived results, some markets are selected to conduct a questionnaire survey
and to examine the controlling factors of location. Based on analysis of
derived data by using Microsoft Excel database, markets location is
evaluated. The results reveal that markets are systematically (in hierarchical
and functional pattern) located in Thingangyun Township. This pattern is
controlled by accessibility, preference based on specific items, and sellers'
strategy of business.
Introduction
Market is defined as an occasion when people buy and sell, an opened
area or building where people to do this (Oxford Advanced Learner's
Dictionary 8th edition CD-ROM, 2010). Location of markets are very
complicated than simply defined by supply and demand Its location was
controlled by others such as social, infrastructure, relative location, etc. Thus,
research question are defined as follows.
Research Question
(1) Does spatial distribution of market vary in terms of size and function?
(2) What are the major controlling factors of market location?
1
2
Dr., Lecturer, Department of Geography, Dagon University.
Graduate Student, Department of Geography, Dagon University
280
Research Hypothesis
(1) Spatial distribution of market varies in term of size and function
within a particular area.
(2) Above variations are generated by the demand (people and status of
people); supply (type of selling goods and way of selling- retail of
wholesale); infrastructure (ways and number of transportation
facilities), government policy (concern with establishment,
restriction, encouragement of markets)
Data and Method
First research hypothesis is that there are variations in the distribution
of markets in terms of function and size in the study area. To proof this
hypothesis secondary data are collected from Market Department, Yangon
City Development Committee. By using ArcGIS 10 software, above data were
depicted as distribution map for visual and preliminary analysis.
Second research hypothesis is related to the controlling factors of
above market distribution variation. In order words, it is concerned with
location factors of markets in the study. There are four major hypotheses for
controlling factors of markets location: demand, supply, infrastructure
(accessibility to market) and government policy.
To analyze the demand factor, Person's Product Moment Correlation
Coefficient Method was used in this analysis. Furthermore, structured
interviews were conducted to 293 customers from 7 markets.
As supply factor, sellers from each market were interviewed about
their purchasing linkages and customer linkages in spatial regions. Altogether,
443 sellers were interviewed to examine the supply factor.
To examine the infrastructure aspect, number of bus line, number of
buses and average number of passenger were collected from Yangon Region
Traffic Control and Management Committee. Then these data was analyzed
together with total shop number of each market by using Person's Product
Moment Correlation Coefficient Method.
281
Geographic Bases of the Study Area
Geographic bases of an area are important factors for the development
of the area. Geographic bases include both physical and human aspects.
Location, size, shape and boundaries
Thingangyun Township is included in Yangon City, Yangon Region.
It is one of the 44 townships within Yangon Region (Figure 1 and 2). It is
located between 16˚ 48' 30" and 16˚ 52' 20" North Latitudes and 96˚ 10' and
96˚ 13' 15" East Longitudes. The township area is 11.4 square kilometre (4.4
square miles). It has a nearly compact shape. It is bordered by Dagon Myothit
(South) Township on the east, Thaketa and Dawbon townships on the north,
Yankin and Tamwe townships on the west. Ngamoeyeik and Baukhtaw creeks
are the natural boundary. Yadana Road is boundary between Thingangyun and
Okkalapa townships. Thingangyun Township comprises 38 wards (Figure 3).
Figure 1 Location of Yangon Region
in Myanmar
Source: Survey Department, Yangon.
Figure 2 Location of Thingangyun Township
in Yangon City
Source: GIS lab, Department of Geography, Dagon
University.
282
Figure 3 Location of Thingangyun Township Residential and Wards
Source: Based on data derived from Township Administration Office.
Human factors
The study area is one of the densely populated areas because it is
located in flatland area and on the trade route that connects between Yangon
and other regions.
Total population and population growth rate
The total population of Thingangyun Township was 1538 persons in
1921 and it increased to 141209 persons in 1973. It was further increased to
193973 persons in 1983. But the population decreased to 151365 persons in
2001. It is because Michaung Kan (1), (2), (3), West Kyeikasan and
Thumingalar wards were relocated from the Thingangyun Township to
Hlaingtharyar and Dagon Myothit townships. In 2011, the total population of
study area was 188293 persons.
Population distribution and density
Topography, economic and transportation conditions of the study area
are favourable for evenly distribution of population.
283
Figure 4 Population Density Distribution by Ward in Thingangyun Township
Source: Township Administration Office, Thingangyun Township
In 2011, its density increased up to 16517 persons per sq. kilometre
(Figure 4). Densely populated ward was U San Phe. It has 55427 persons per
sq. kilometre in 2001 and 66795 persons per sq. kilometre in 2011. It is the
highest population density area for a long time. It is because the ward has
good job opportunities and good transportation accessibilities. The lowest
density area was Mi Chaung Kan I with 2287 persons per sq. kilometre in
2001. Thut Wie Gyi ward also has population density of 4274 persons per sqkilometre in 2011 because of low accessibility.
Types of Markets and Shops
Market Types
The study area has 6 permanent markets and 3 street vendor markets.
Permanent markets and their locations are as follow:
(1) Thingangyun Market located on the Lay Daunkkan Street (U
San Pane),
284
(2) Buda Market located on the Thingangyun Buda Asha Street &
Pyidawtha Street
(3) Sanpya Ngamoeyeik Market located on the Lay Daunkkan
Street (Ngamoeyeik),
(4) Thuwana Market located on the Thanthumar Street (29 Ward),
(5) 16 Yadanar Market located on the Yadanar Street and Thudana
Street,
(6) Yenathar Market located on the Lay Daunkkan and Thuwana
Street (24 Ward).
The morning street vendors are:
(1) Bawga Market on the Aathintyte Street.
(2) Kabukwe Market on the Yupa Street (Nga/ Ka)
(3) Lay Daunkkan Market on the Lay Daunkkan Street.
Shop Types
Markets of Thingangyun Township are categorized as follows:
(1)
Meat and vegetable are the items that customers need to buy on
daily basis. It includes all types of meat and vegetables, fruits
and items that can perishable without refrigeration.
(2)
Grocery goods and dry goods include milk, sugar, beverages
(like tea and coffee), rice, oil, salt, dried fish, bean, etc. which are
used in kitchen and could keep under natural environment for
some period without refrigeration.
(3)
Clothes and garments refer to all items of cloths, bags, and
fabrics. Those items are usually purchased only two or three
times a year for average income person.
Medicines and cosmetics usually are rarely needed than the
above mentioned three items. Cosmetic is also referred to as
luxury good. It is not a basic requirement for low income people.
Hardware and electronic goods are sometimes referred to as
construction goods that are needed in construction and
renovation of houses.
(4)
(5)
(6)
(7)
285
Gold and jewellery are the items that only high income persons
can afford and its purchase interval is much large than the above
mentioned items.
Others items include items that are not classified in above
mentioned categories.
Variations in Number of Shops and Shop Types in Thingangyun
Township
Variations in Number of Shops among the Permanent Markets
Sanpya Ngamoeyeik Market has the largest number of shop and Buda
Market has the smallest number of shop. Sanpya Ngamoeyeik Market has
1152 shops while Buda Market has only 21 shops. When a market has good
accessibility, people from a long distance will come to the market.
Variations in shops type within the permanent markets
Sanpya Ngamoeyeik Market comprises 174 meats and vegetables
shops, 386 grocery shops, 280 cloth and garment shops, 140 medicines and
cosmetics shops, 84 gold and jewellery shops, 56 hardware and electronic
goods shops and 32 others shops. Thingangyun Market includes 69 meats and
vegetables shops, 188 grocery shops, 230 cloth and garment shops, 75
medicines and cosmetics shops, 150 gold and jewellery shops, 59 hardware
and electric goods shops and 15 others shops. Thuwana Market has 99 meats
and vegetables shops, 213 grocery shops, 112 cloth and garment shops, 77
medicines and cosmetics shops, 52 gold and jewellery shops and 44 hardware
and electronic goods shops. 16 Yadanar Market includes 120 meats and
vegetables shops, 114 grocery shops, 30 cloth and garment shops, and 2 gold
and jewellery shops. Yenathar Market comprises 83 meats and vegetables
shops, 150 grocery shops, 22 cloth and garment shops, and 15 other shops.
Buda Market has 21 grocery shops.
Sanpya Ngamoeyeik, Thingangyun and Thuwana markets have the
highest level function and support all kind of items that customer need. On the
other hand, Yenathar and 16 Yadanar markets serve only with meat and
vegetable, grocery and dry goods, and clothes and garment. Thus, it is
localized market and customers who need to buy cosmetic and gold, etc. have
286
to use higher level market like Sanpya Ngamoeyeik Market. Buda Market
only has grocery and dry goods shop.
Variations in total number of shops among the street vendors
Lay Daunkkan Market comprises 50 grocery and dry shops and 20
meat and vegetable shops. Bawga Market comprises 30 grocery and dry shops
and 10 meat and vegetable shops. Khabukwe Market includes 50 grocery and
dry shops and 19 meat and vegetable shops.
Variations in type of shops among street vendors
Each street vendor market, most of them are selling only meat and
vegetables and grocery and dry goods are not variation in the ratio of these
two types of shops. It reveals the fact that street vendors have developed based
on the local customers' daily needs.
Spatial Variations the Distribution of Markets in Thingangyun Township
The Yangon City Development Committee designated the level of
markets based on the type of building and items sold in the market. All 9
markets are established before 1975. Yenathar Market has the largest area
with 11769.70 square metre and Khabukwe Market is the smallest market
with 515.62 square metre. A level markets are all brick buildings, while the
building materials of and B level markets are timber and iron sheets (Table 1).
Distribution of markets
To clearly understand the spatial and functional variations of markets
in the study area, it is necessary to map the distribution of markets. Figure (5)
shows the distribution of markets by their level and size. It reveals that A, B
and C level markets are distributed in a relatively dispersed pattern. From this
map, it can be interpreted that location of markets involves spatial as well as
functional factors.
287
Table 1 Some Facts of Markets in Thingangyun Township
Market Name
Area
Year of
Market
(Sq. meter) Establishment Level
Building Type
Number
of Shops
Sanpya
Ngamoeyeik
Market
Thingangyun
Market
Thuwana Market
9290.30
1975
A
Brick building & 2
Storey
1152
7993.10
1952
A
786
5354.93
1975
B
Brick & 4 Storey
(timber& Iron Sheet)
14 buildings
Yenathar Market
11769.70
1975
C
270
16 Yadanar Market
6296.04
1974
C
Buda Market
1114.84
1957
C
8 buildings (timber &
Iron Sheet)
4 buildings (timber &
Iron Sheet)
timber & Iron Sheet
557.42
1974
D
Roadside
70
515.62
1207.74
1963
1974
D
D
Roadside
Roadside
69
40
Lay Daunkkan
Market
Khabukwe Market
Bawga Market
Figure 5. Distribution of Markets in Thingangyun Township
Source: Based on the data obtained from Market Department, Yangon City
Development Committee.
648
266
21
288
Variations of functions among the markets
Figure (6) from this map it is clearly understands that large markets of
Sanpya Ngamoeyeik, Thingangyun, and Thuwana are located in triangle
location to cover the whole township. These three large markets have all
functions (items) to support the residents of township. Apart from that 16
Yadana and Yenathar markets are located to take some intervening
opportunity of above three large markets. But these medium size markets
could not supply all items that are available is large markets. Again, Bawga,
Khabukwe and Laydaukkan markets take the advantage of remaining
intervening opportunity by locating at the intermediate distance of above large
and medium markets. In general, this map clearly depicted the hierarchical or
functional variation in location of market in an area.
First, population factor was examined in terms of total population and
population density. Then, customer preference and seller type were analyzed
by using data derived from questionnaires survey. Finally, accessibility of
each market was analyzed as an infrastructure for location of market.
Figure 6 Variations in Markets by type of Commodities Sold
Source: Based on the data derived from Market Department, Yangon City
Development Committee.
289
Factors Controlling the Distribution Pattern of Markets
Commodities can be categorized into different groups based on
frequency of buying by customers. There are daily consumption goods, luxury
goods, wealth and long-term consumption goods with different buying
frequency. Since daily consumption goods have to buy on daily basic, the
market should be located within the range of short distance. It is because large
number of people has to commute to this kind of market daily. On the other
hand, luxury good and expensive goods are bought only once or twice a year.
Then, when customers buy these good, they are more selective and buy by
travelling a long distance.
Economic theories mainly considered population and status of
population as main factor of demand and location of market. However, as
examined in previous chapter there are hierarchical differences among the
market and their location. Thus, this chapter examines the possible controlling
factors of market location in study area. First, population factor was examined
in terms of total population and population density. Then, customer preference
and seller type were analyzed by using data derived from questionnaires
survey. Finally, accessibility of each market was analyzed as an infrastructure
for location of market.
Population as a factor of demand and markets location
Figure (7) shows the population density by wards in study area.
Location and size of markets are also depicted on the same map. From this
map it is difficult to conclude that distributions of market are related to the
population of ward where market is located. To examine more detail
Pearson’s Product Moment Correlation Coefficient Analysis was conducted.
Variable used in this analysis are shown in Table (2). Correlation coefficient
value (r2) between the total number of shop and population of ward where
market located is (0.35). It reveals that population and number of shop are
fairly related. Percentage of explanation (r2) is (0.12) or 12 percent. Thus, 12
percent of market location could explain by population of the ward where
market is located. As second variable, population density was used in
correlation analysis. By using population density instead of population itself,
area related bias could be eliminated in the analysis. The resulted correlation
coefficient between number of shop in market and population density of the
ward is (0.116). It shows that there is no or very few correlation among the
two variables.
290
Figure (7) Population Density and Location of Markets
Source: Market data are derived from Market Department, YCDC and population data was
obtained from Thingangyun Township Administrative Office.
Table (2) Relationship between number of shop and population
Name of
Markets
Lay
Daunkkan
Market
Number of
Population
Shops
Pop_
Density
Ward
70
7027
9101
Lay Daunkkan
Sanpya
Ngamoeyeik
Market
1152
8443
31875
Ngamoeyeik
Thingangyun
Market
786
3114
25161
U San Phe
Thuwana Market
648
12318
547
16 Yadanar Market
266
7432
86518
16/1, 16/2
Yenathar Market
270
4643
3350
Thuwana 24
Thuwana 29
291
Name of
Markets
Number of
Population
Shops
Pop_
Density
Ward
Buda Market
21
7115
12548
Khakwe
Khabukwe Market
69
3114
25161
U San Phe
Bawga Market
40
3770
5380
Zakwe (South)
Source: Market data are derived from Market Department, YCDC and population data was
Township Administrative Office
Thus, population density could not contribute to the location of
markets. From above correlation analysis it could be confirm that location of
market is not strongly determined by the population. In that case, it is worth
considering another two points: its location between Yangon CBD and
periphery of Yangon City and rural area; and infrastructure (accessibility) of
the market. These two points could generate the hierarchical market
development that could not explain by population.
Customer’s aspect on markets location
Questionnaires surveys were conducted to customer from various
markets. Altogether 293 customers were interviewed from 9 markets. It is
reveals that 180 out of 293 respondents (61 percent) buying meats and
vegetables, 66 persons (23 percent) of customer buying grocery, 18 persons (6
percent) buying the cloth and garment, 13 persons (4 percent) are buying food
and soft drink, 10 persons (3 percent) buying cosmetic and medicine, 3 person
(1 percent) buying electronic and hardware goods and 3 persons (1 percent)
buying the gold and jewellery (Figure 8). It is clear that classification of goods
used in the previous explanation has consistency with actual buying pattern of
customers.
Customers generally have similar purchasing behaviors in Myanmar. It
is because the use of refrigerator is not common pattern in Myanmar. They
purchase meats and vegetables for daily consumption, grocery for medianterm consumption, cloth and garment for long-term consumption, cosmetic
and medicine for occasional consumption, gold and jewellery for very
infrequent consumption. For gold and jewellary purchase customers use large
market such as Sanpya Ngamoreyeik Market.
292
Figure 8 Customers Buy Type of Purchasing Items
Source: Based on Structured interview, February, 2012 (n= 293)
Analysis from the point of view of sellers
To understand the spatial and function variations of the markets in the
study area, questionnaires surveys were conducted to seller from all markets.
Altogether data from 443 sellers were collected during the survey (Figure 9).
To generalize the functional differences, 9 markets were categorized
into 3 groups: large markets, medium markets, and small markets. Large
markets include Sanpya Ngamoeyeik, Thingangyun and Thuwana markets.
Medium markets include 16 Yadanar and Yenathar. Small markets are
Laydaukkan, Bawga, Kabukwe and Buda.
Large markets have all type of selling. To further understand the
function of markets in the study area seller from different markets are asked
about the source of their selling materials. Seller from small markets bought
their selling material from the large markets located within the Thingangyun
Township. On the other hand, sellers from large markets bought the goods
from Nyaungbinlay and Mingalar markets. Sellers from medium size markets
have bought their good from various markets and also from producers
mentioned in the other category. This point also supports the function
variation of markets within the Thingangyun Township.
Finally, sellers are asked about the estimated location of customer
buying in their shops. More than 97 percent of customers come from the same
293
ward where market is located. In case of medium market, about 94 percent
come from the same ward and 5.56 percent of customers come from the
Thingangyun Township. Large markets have their customer not only within
the ward but from the Thingangyun Township and other townships related to
the Thingangyun Township.
Figure 9 Different Levels of Markets with Commodities Obtained from Different
Sources
Source: Based on Structured interview, February, 2012 (n= 443)
Transportation infrastructure as a location factor of markets
As observed in previous section, population of each ward alone could
not well explain the location of market. In some markets like Sanpya
Nagamoeyeik Market, majority of customer could come from townships of
Dagon Myothit and villages included in the Hlegu Township. Thus, it is
necessary to consider the transportation infrastructure of each market.
To get the total passenger number, total number of trip in each bus line
passing the specific market was multiply by number of passenger that a bus
could carry in average. Then, total number of passenger for each bus line was
summed up to get the total number of passenger passing each market.
The average number of passenger used in this analysis was as follows:
Special Large Bus
Large Bus (ordinary)
Chevrolet (Bikepu)
Dyna Truck
Hilux Pickup
– 60 passengers
- 50 passengers
- 45 passengers
- 40 passengers
- 20 passengers
294
Table (3) shows the relationship between number of shop and number
of bus line, number of shop and total number of bus, and total number of shop
and to total passenger passing each market.
Table 3 Relationship between Number of Shops and Transport Facility
No. of
Shops
No. of Bus
Lines
Total No. of
Buses
1152
59
7538
Thingangyun Market
786
29
3500
161544
Thuwana Market
648
21
2412
115572
Yenathar Market
270
21
2412
115572
16 Yadanar Market
266
6
844
31290
Lay Daunkkan Market
70
29
3500
161544
Khabukwe Market
69
1
340
13600
Bawga Market
40
0
0
0
Buda Market
21
1
340
13600
Markets Name
Sanpya
Market
Ngamoeyeik
Total
Passengers
344518
Source: Calculated based on data obtained from All Bus Line Control and Management
Committee of Yangon Region (2012).
-
Correlation coefficient between No. of shop and No. of bus line =
0.839 (r2= 0.703)
-
Correlation coefficient between No. of shop and total No. of bus =
0.997 (r2= 0.995)
-
Correlation coefficient between No. of shop and total passenger =
0.999 (r2= 0.998)
From above result, it is reveals that the variation in number of shop is
very highly explained by the number of bus line (r2= 0.703), the number of
bus (r2= 0.995), and total passenger (r2= 0.998). In case of Sanpya
Ngamoeyeik Market, 7 bus lines that connect Thingangyun Township and
other townships such as Hlegu and Bago are passing through. Thus, this
market is not only serve the local people living around the market but also for
people living in the Thingangyun Township and other more distance
townships.
295
In case of Buda Market, 10 circular trains and 5 local trains daily stop
at the Buda Station near the market. Originally, the name of market is derived
from the Buda Station where meats and vegetables that carry from regional
area to Yangon City were drops and sell. Thus, location of this market is
originally more railway specific than road transport. But at present there is
one Dyna Truck bus line with 35 buses and running 340 trips near the market.
Thus, from above analysis, it is very clear that transportation infrastructure is
very important for the location of markets in Thingangyun Township.
Conclusion
This paper analyzes the distribution pattern in Thingangyun Township
by using data obtained from market department, Yangon City Development
Committee. The controlling factors of market location are further found out by
using data collected from questionnaire surveys to sellers, structured
interviews to customers, and data obtained from Yangon Region Traffic
Control and Management Committee. ArcGIS 10 software and Microsoft
Excel software are used in the analysis. To find out the relationship between
total number of shops and population, population density, number of bus lines,
number of buses and passengers passing through the markets, Pearson's
Product Moment Correlation Coefficient Analysis is used. Analysis of
distribution of markets reveals:
(1) Markets are systematically (hierarchical and functional) distributed
in Thingangyun Township. Some markets serve the residential
wards, while others serve the whole township of even more wider
region, including rural areas of Yangon Region
(2) Above distribution patterns could not explain the population served,
but customer's preference based on buying items
(3) Sellers also vary in each market, in terms of type of sale, selling
type, and sources of commodities purchased
(4) Location of markets in the Thingangyun Township can effectively
explain by means of accessibility
Acknowledgement
I would like to express my deep gratitude to Dr Aung Kyaw, Professor, Department
of Geography, Dagon University and for his kind permission to conduct this research paper
and proper guidance.
I would also like to acknowledge the U Aung Soe, Head of Deputy offices, Market
Department, Yangon City Development Committee, Daw Than Than Htay, Junior Officer,
Market Department (Pazuntaun Market), Yangon City Development Committee, U Win Zaw,
296
Head of Officer (Second), Bus Control Committee, Yangon Region and all those who have
helped in the collection of data and information from different sources.
References
Hnin Lei Lei Win (2008): A case study of the health care and problems of dengue
haemorrhagic fever (DHF) in Thingangyun Township within Yangon
City, (Unpublished PhD Dissertation, Department of Geography,
University of Yangon).
Thingangyun Township Administration Office (2011): Facts and figures of Thingan Kyun
Township, (Yangon Region).
Yangon Region Traffic Control and Management Committee (2012), General report of bus
lines, number of bus lines, name of bus lines, terminals and total
number of bus stops in Yangon Region, (Yangon Region).
Geographical Analysis on the Socio-economy of Coastal Area:
the case of Daminseik Village, Mon State
Kyaw Kyaw
Abstract
This paper is intended to analyse the economic activities and social
conditions of Daminseik Village. It is situated in Setsé Village Tract,
Thanbyuzayat Township, Mon State. Setsé is one of the famous beaches of
Myanmar. Daminseik Village is located on the west of over 1.6 kilometres
away from Setsé. It is about 4 metres above sea level. It has an area of about
4.86 hectares (about 12 acres). In ancient time Mon settlers established in
this small fishing village. Now most of the people are Bamar and they came
from some villages in central Myanmar. Some people are Mon and Kayin.
Total population of Daminseik Village is 700 persons in 2011. This area has
no agricultural land. Most of the villagers conduct fishing and related
activities. Some people are skilled fishermen and workers. They are from
other villages in Mon State. Fishes are preserved to fish-paste, prawn-paste,
fish sauce and dried fish. These preserved fish export to Yangon, Pyay and
Mandalay at every month. The economy of this study area mostly depends
on the fishing and related activities. This area has no waterway. Therefore
local people and preserved fish products rely mainly on land transportation.
Key words: small fishing village, fishing and related activities, skilled
fishermen, no waterway
Introduction
This paper is intended to analyse the economic activities and social
conditions of Daminseik Village. Daminseik Village is in Setsé Village tract,
Thanbyuzayat Township, Mon State. Setsé is one of the famous beaches of
Myanmar. Daminseik Village is located on the west of Setsé. It is about 4
metres (about 12 feet) above sea level. This area a small fishing village. The
economy of this study area mostly depends on the fishing and related
activities. Total population of Daminseik Village is 700 persons and
population density is over 38,000 persons per square mile in 2011.
Objectives
The objectives of this paper are:
(a) to examine and analyze the present site and situation of Daminseik
Village
(b) to express the economic activities of Daminseik Village and
Lecturer, Dr., Department of Geography, West Yangon University.
298
(c) to analyze the socio-economy of Daminseik Village
Data and Methodology
For primary data, interview, questionnaires and open talks are
conducted together with in field observations during very short period, and
secondary data such as maps and other documents are taken from various
sources: Department of Geography (Mawlamyine University), Thanbyuzayat
Township Administrative Office, Daminseik Village Administrative Office
and Google image for location of Daminseik Village. Procedures of the field
survey and study are:
First, the present site and situation of Daminseik Village are observed.
Open talks with some local people are conducted and then the photographs are
taken. Second, there are about 180 houses, of which 50 houses (50
respondents) are selected randomly and make open talks and give them
formatted questionnaires. Finally, data from questionnaires are analysed by
using appropriate calculation method and to assess the questionnaires and
open talks responses concerning about the socio-economic condition.
General Physical Features
Daminseik Village is situated on the northwestern part of the Setsé and
on the coastal lowland of Mon State. It is located between 15º 56' 53" and 15º
57' 11" North latitudes and also between 97º 36' 15" and 97º 37' 19" East
longitudes. It is one of the villages in the Setsé village tract, Thanbyuzayat
Township. This Township has two towns (Thanbyuzayat and Kyaikkhami), 26
village tracts and 69 villages.
Daminseik Village is bounded on the north and west by Kayinthaung
Village tract, on the east by Setsé and on the south by the Mottama Sea.
Daminseik Village has an area of about 4.86 hectares (about 12 acres). The
shape of the study area is elongated shape. Daminseik Village is situated on
the coastal lowland of Mon State and it is about 4 metres (about 12 feet)
above sea level. This area is gently sloping into the south. The main drainage
of this area is Kyonemayoe Chaung and Setsé Chaung. These streams flow
from north to south into the Mottama Sea. These are tidal creeks in this area.
Figure 1.
Study area has no weather station. Therefore temperature and rainfall
data are based on Meteorology and Hydrology Department, Thanbyuzayat, in
2011. This is a hot wet region; the chief source of rain is the Southwest
Monsoon. According to table 1, the average maximum temperature is 33.29ºC
299
and average minimum temperature is 27.27ºC. Average mean monthly
temperature is 21.41ºC. The hottest month is April and January has the lowest
temperature. The mean temperature in April is 31.29ºC and in January
25.05ºC. Thus the range of temperature is 6.24ºC. Table 1 and Figure 2.
Figure 1. Location and Physical Features of Daminseik Village
Source: Based on Google Earth and Administrative Office, Daminseik Village and
Thanbyuzayet.
Daminseik Village enjoys abundant rainfall due to its coastal location
and surface configuration. The rainy season is from the second week of May
to the last week of October. Scanty and unseasonal rainfall may occur in
300
November, December and January due to depressions and cyclones in the Bay
of Bengal. Rainfall regime is from end of May to first week of October and
the periodical rainfall is abundant. A week or ten days of incessant rain is not
uncommon in June, July and August. Interlude of sunshine and cloudy sky
also occur during the rainy season.
Table 1. Monthly Temperature and Rainfall of Daminseik Village (2011)
Maximum
Temperature
(ºC)
Minimum
Temperature
(ºC)
Mean
Temperature
(ºC)
1. January
33.00
17.11
25.05
4.83
2. February
35.51
17.98
26.75
12.95
3. March
36.66
20.85
28.51
29.97
4. April
36.30
26.28
31.29
90.01
5. May
35.24
22.39
28.66
501.91
6. June
29.83
22.74
26.17
832.11
7. July
30.78
23.19
26.99
1207.01
8. August
29.82
22.96
26.38
1230.89
9. September
31.36
23.11
27.23
641.09
10. October
33.43
23.10
27.88
128.02
11. November
34.00
19.82
26.91
38.10
12. December
33.51
17.42
25.46
3.05
33.29
27.27
21.41 Total = 4719.94
No.
Month
Average
Rainfall
(mm)
Source: Meteorology and Hydrology Department, Thanbyuzayat (2011).
301
2200
40
2000
1800
32
1400
24
1200
1000
16
800
Temperature ( ºC )
Rainfall ( mm )
1600
600
8
400
200
0
0
Jan
Feb
Mar
April
May
June
July
Aug
Sept
Oct
Nov
Dec
Months
Rainfall
Maximum Temperature (ºC)
Mean Temperature (ºC)
Mini Temperature (ºC)
Figure 2. Temperature and Rainfall Condition of Daminseik Village
Source: Based on table 1.
The variation of rainfall amount depends on the strength of southwest
monsoon and occurrence of depressions and cyclones in the Bay of Bengal.
Within a period of 34 years from 1968 to 2003, the highest amount of total
rainfall of 7109.47 mm occurred in 1994. The least annual rainfall recorded
was 3573.78 mm in 1969. June, July, August, and September receive highest
rainfall. Daminseik Village receives 4719.94 mm of total rainfall. Therefore
this study area enjoys tropical monsoon type of climate.
The whole Myanmar landmass was situated under sea level in the last
500 million years ago. According to Geologists, this time is called Ordovician
period. In Late Ordovician period, tectonic processes had appeared by the
volcanic eruptions under sea level. Myanmar landmass was raised above sea
level because of folding mountain systems. Some areas of Shan Highlands and
Tanintharyi mountain systems had appeared above sea level during Permian
period. According to this hypothesis, Setsé environs existed during last 200
million years ago. According to the historical record of Setsé Kyaiksaw Yale
Pagoda, this area was assumed that older sedimentary rock. Therefore
302
underlying rock is laterite. Most of the areas are covered by sandy loam soils
and sandy soils.
General Human Factors
In ancient time Mon settlers established in this Setsé area and its
environs. Setsé area is one of the village tracts in Thanbyuzayat Township. It
is bounded on the north by Kyonkadat Village tract, on the east by Pagna
Village tract, on the west by Kayinthaung Village tract and on the south by the
Mottama Sea. Setsé Village has an area of about 2173.6 hectares (about 5,371
acres). The widest width is about 4.99 kilometres (about 3.1 miles) from east
to west and longest length is about 6.73 kilometres (about 4.2 miles) from
north to south. There were 1,097 houses and 1,140 households in Setsé
Village tract. Population of Setsé Village tract is about 3,337 persons (1,656
males and 1,681 females) in 2011.
Daminseik Village is situated on the coastal lowland Mon State.
Daminseik Village is over 2.4 kilometres (over 1.5 miles) away from Setsé
and time distance is nearly 10 minutes by Bicycle. In ancient time Mon
settlers established in this small fishing village. Some Mon people moved to
Thailand for their livelihood since 1985. These people are working ages of
this village. Now most of the people are Bamar and they are transferred from
some villages (especially villages near Pyay and Magway) in central
Myanmar. Very little indigenous people are Mon and Kayin. It has about 180
houses and 700 persons (343 males and 357 females) in 2011. Average family
member size is about 4 persons per house.
In the study area, most of the people are Bamar and some people are
Mon and Kayin. All of the people are Buddhist in religion. There is one
Monastery in this area. There is only one Basic Education Primary School in
Daminseik Village. This school building was rebuilt and reopened at 1st June
2009. It has an area of 0.66 hectare (about 1.64 acres). There are 6 teachers
and 2 Kindergarten teachers in this school. Over 300 students are attended to
this Primary School. Teacher student ratio is 1:50. Plate 1.
In this village, there is no clinic and rural health care centre. It has only
one head of the health servant. People also rely on traditional medicines and
practitioners of indigenous medicines. Some unfit people go to the Setsé
Hospital for their health.
303
Factors Supporting Human Settlement
Water Supply
There are some artesian wells in this village but these wells supply no
fresh water every time and some supply within rainy season. Plate 2. There is
no tube well and no fresh water supplies during dry season in Daminseik
Village. For drinking and cooking, fresh water is bought and carried from
Kayinthaung Village and Setsé. Fresh water six gallons cost about 100 Kyats.
For households and other domestic uses, water sources are sea water and tidal
creek such as Kyonemayoe Creek. Plate 3.
Plate 1. Daminseik Basic Education Primary School
Field Notes: Old building and New building
Plate 2. Sources of Fresh Water in Daminseik Village
Field Notes: some artesian wells supply no fresh water every time and some are very
low water level and no water during dry season.
304
Plate 3. Source of Fresh Water from Kayinthaung and Setsé
Field Notes: Children carry fresh water with six gallon plastic bucket.
Electricity Supply
There is no Government Electricity Supply Board in Daminseik
Village. There are two private electricity supplies in this village. They have
two diesel engines. Electricity supply distributes to two times a day. These are
morning and evening time. The first time is 4:30 a.m. to 6:00 a.m. and second
time is 6:00 p.m. to 10:00 p.m. Most of the houses use average one light bulb
and one set of Television. The cost is about 200 Kyats for one light bulb and
about 400 Kyats for one set of Television per day. Average cost for electricity
uses is between 10,000 and 15,000 Kyats for each house per month. Plate 4.
Plate 4. Supply of Private Electricity for Whole Village
Field notes: Electricity supply poles and string of cable wire connected with houses and
food shop.
305
Communication and Transportation
There are about ten CDMA 450MHz phones in Daminseik Village.
Most of the villagers rely on these communication facilities. All of the house
own electronic facilities such as Radio transmitter, Television set and VCD or
DVD or EVD set. Weather information is derived from Radio Stations and
MRTV.
This area has no waterway. Therefore people of the Daminseik Village
rely mainly on land transportation. Transportation cost is about 500 Kyats
from Setsé to Thanbyuzayat and about 1500 Kyats to Mawlamyine by bus.
There are about 12 bicycles, 20 motorcycles and 5 trailers in Daminseik
Village. Time distance is about 30 minutes and about 16.1 km (over 10 miles)
away from Setsé to Thanbyuzayat and nearly 2 hours and about 80.5
kilometres (over 50 miles) away from Setsé to Mawlamyine.
Analysis on Socio-Economic Activities
This study area is situated on the coastal lowland of the Mottama Sea
and it has a wide spread of sea water. Therefore sea-fishing activities are main
economic activities of the study area. This village was built at during last 100
to 150 years ago. This area was settled from fishermen. These are Mons,
Bamars and Kayins. At first Mon people are highest numbers and now highest
numbers are Bamar. These Bamar are transferred from central Myanmar and
Mon State. Daminseik Village has about 180 houses and 700 persons in 2011.
Of which 50 houses are selected and got 50 responses from these formatted
questionnaires during the very short period. These respondents are over 7
percent of the village population but they are heads of the household. Table 2
and Figure 3.
Table 2. Working Condition of Respondents in Daminseik Village
Sr.
No.
1.
2.
3.
4.
5.
6.
7.
Types of Work
Fishing
Preserved fish
Fishing Boatman
Random work
Sellers
Rubber Plantation
Driver
Total
Numbers of
Worker
24
8
5
6
4
2
1
50
Source: Based on Field Survey, 2011.
Percentage
48
16
10
12
8
4
2
100
306
Figure 3. Working Condition of Respondents in Daminseik Village
Source: Based on table 2.
According to above table, nearly 48 percent of the respondents
conduct fishermen and about 10 percent conduct fishing boatmen. About 16
percent of the respondents are the workers of the fish-paste sheds and dried
fish stages. Therefore nearly 75 percent of respondents (37 respondents) are
fishing and related activities. Rest of the respondents works in other economic
activities. Of these about 12 percent are in random works. Nearly 8 percent of
the respondents are hawkers. These hawkers sell fried-fish and prawns,
Myanmar delicacy, other snacks and foods at Setsé beach.
Three main types of economic activities are found in study area. These
activities are related to site and situation of the coastal area and local people
within this area. These are fishing and related activities, retail-sale, and other
economic activities. Figure 4.
307
Figure 4. Flow chart of the Economic Activities
Source: Based on Field Survey, 2011
(1) Fishing and Related Activities
Daminseik Village is situated on the coastal lowland of Mon State.
Therefore people of this area conduct fishing and related activities. There are
about 6 fish-paste sheds and average workers are about 6 to 7 persons per each
shed. Average salary for each worker is about 60,000 Kyats. There are about
50 small fishing engine boats in this village. A licensed fee for one fishing
engine boat is 30,000 Kyats per year. Each fishing boat cooperates with nearly
6 or 7 fishermen. Fishing activities are done at once two weeks. Fish caught is
done by twice a day. One time is early morning start at 5:00 and another time
is afternoon start at 1:00. One work trip takes time nearly 4 hours. Average
payment for each skilled fisherman is about 60,000 Kyats and each fisherman
is about 40,000 to 50000 Kyats for one month.
Nearly 400 Viss are caught by one trip on each fishing boat. Value of
these fish freight is 500,000 Kyats to 1,000,000 Kyats depending on the type
of fish. These fishes are caught by conical fish net set (Kya net) which against
the current. Caught fishes are Ngashwei (golden hued pike conger–
308
Muraenesox telabonoides), Ngaphe (featherback–Notopterus notopterus ),
Ngabudin (puffer fish or globe fish– Diodon hystrix) and Kakujan (tassel fish–
Polynemus spp.). Sometime prawns are caught in these fishing boats. These
fishes are sold to the owners of fish-paste sheds. These fishes are preserved to
fish-paste, prawn-paste, fish sauce and dried fish in these sheds and dried fish
stages. Fish are dried onto the dried fish stages. These stages are located at
backward of the village. These stages are temporary huts. There are about 50
temporary huts in this village during November to May. Plate 5 and 6. And
then these preserve fish mainly export to Yangon, Pyay, Magway and
Mandalay. These export items (dried fish, fish-paste, prawn-paste and fish
sauce) sent one time at every month.
Plate 5. Fish-paste Sheds and Big Glazed Earthen Jars
Field Notes: preserved to fish-paste, prawn-paste, fish sauce, dried fish and animal feeds
Plate 6. Dried Fish Stages
Field Notes: fishes were dried on these temporary huts and hang on the poles.
309
(2) Retail-sale Activities
In this study area, there is a temporary market that is opened at every
morning. There are seven small retail sale shops and one food and drink shop
along the road. These shops are attached to the buildings. Rice, edible oil,
noodle, salt, soft drinks, foodstuffs, traditional medicines, drugs, snacks and
other domestic equipments are sold in these shops. For these shops, many
baskets of rice are bought from Thanbyuzayat and other miscellaneous goods
and human needs are brought from Mawlamyine and Thanbyuzayat. Plate 7.
Plate 7. Retail Sale Activities
Field Notes: Misc. goods Shop, Food and Drink Shop on the main road.
(3) Other Economic Activities
There is no agricultural land in Daminseik Village. Most of the areas
are sandy loam and sandy soils. Small numbers of pigs and chicken are raised
in this village. These raised animals are sold for feed. There is only one owner
of Rubber Plantation. This rubber plantation is situated on the SetséThanbyuzayat Road. It has an area of about 10.12 hectares (about 25 acres).
Average 4 hectares (10 acres) of rubber plantation need to work 5 skilled
workers. Average salary for each skilled worker is about 50,000 Kyats and
others are 30,000-35,000 Kyats. Owner of this plantation get about 5,000,000
to 10,000,000 Kyats for one year. Small number of workers works at this
rubber plantation. Another economic activity is fire-wood selling. These firewood get from rubber plant. Fire-wood were used for cooking in this village.
Some people use charcoal for cooking. Plate 8.
310
Plate 8. Other Economic Activities
Field Notes: Fire-wood selling and storing for cooking
Conclusion
Daminseik Village is a small fishing village in Setse Village tract,
Thanbyuzayat Township. Economy of this area depends on the fishing and
related activities. This area has no agricultural land because of sandy loam and
sandy soils area. There are three main types of economic activities in this
village. There are 6 fish-paste sheds in this area and average workers are about
6 to 7 persons per one shed. This village has about 50 small fishing engine
boats in 2011. Each fishing boat cooperates with nearly 6 or 7 fishermen.
Most of the villagers conduct fishing and preserved fish activities. Fishing
activities are done by twice a day. One round trip takes time nearly 4 hours.
These fishes are caught by conical fish net set (Kya net) against the current.
Caught fishes are Ngashwei, Ngaphe, Ngabudin and Kakujan. These fishes
are preserved to fish-paste, prawn-paste, fish sauce and dried fish in these
sheds and dried fish stages. These preserve fish export to Yangon, Pyay and
Mandalay in every month. By product of fish are used for animal feed. This
area is situated on the coastal area. Therefore fishing is the main important
activity for local people but other economic activities are found in this area.
Some people are government servant, owner of foodstuff shop, rubber
plantation owner and workers, hawkers, motorcycle taxi drivers and so on.
People and products of this area mainly rely on road transportation.
Development of economic activities is essential to the development of the
study area.
311
Acknowledgements
I would like to express my heartfelt thanks to Professor Daw Khin Mya Thway
(Head of the Geography Department, West Yangon University), for her kind permission and
encouragement to do this research paper.
Thanks are due to the respective authorities of Daminseik Village Administrative
Office, Thanbyuzayat Township Administrative Office, and the responsible persons and local
people of Daminseik Village for their ready help in data collection and willing responses to
open talks.
References
Meteorology and Hydrology Department (2011): Temperature and Rainfall Data,
Thanbyuzayat Township.
Thanbyuzayat Township Administrative Office (2011): Regional Report for Thanbyuzayat
Township, Thanbyuzayat, Mon State, February 2011.
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armfvjrdKifc&dkif? oHjzLZ&yfjrdKUe,f/ yHkESdyfomoema&;OD;pD;Xme? omoema&;0efMuD;
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Migration Patterns of Hpa-an Township
Saw Yu May1, Hnin Khaing Aye2
Abstract
Migration is the act or process of moving from one place to another with the
intent of staying at the destination permanently or for a relatively long
period of time. Population growth and decline is concerned with migration
process as one of factors. Hpa-an, a capital of Kayin State, have
experienced migration process in last decade and is still increasing in this
process. Hpa-an Township is situated in the mid-western part of Kayin
State. It lies between North Latitude 16 º 30' and 17 º 44', East Longitude
97º 21' and 98 º 01'. The area of Hpa-an Township is 1120 square miles and
comprises Hpa-an Town and 91 Village Tracts. Hpa-an Township is fairly
populated. The total population of Hpa-an Township is 451851 persons and
the density of population is 403.4 persons per square mile in 2011. In Hpaan Township, people move from their home to another country for purposes
of jobs. In this study, the main problems could be addressed as how and
why the people are migrating in Hpa-an Township? The purpose of this
paper are : to study the migration pattern of Hpa-an Township, to present
the main reasons of this migration, to observe distance bias and directional
bias pattern of Hpa-an township, to assess the changes of occupation
structure of migrants of Hpa-an Township. To obtain the relevant data,
structured interview survey method was used.
Key words: Migration Patterns, distance bias, directional bias, pull factor,
push factors
Introduction
Migration is the act or process of moving from one place to another
with the intent of staying at the destination permanently or for a relatively
long period of time (1992, Longman). Some time it refers that people make a
movement from one area (usually their home area) to work or settle in another
places. At basic factors, migration takes place because the migrants believe
that their opportunity and life circumstances will be better at their destination
than they are at their present location. Nevertheless, if an area where takes
place a movement of in-migration because of positive condition, that will
increase the population or human resources, or if takes places a movement of
out-migration because of negative condition, it will lose their population or
human resource. This condition has occurred within a young or adult people,
and it affects the negative impacts to this area. In Hpa-an Township, migration
1. Dr., Lecturer, Department of Geography, Taunggyi University.
2. Dr., Assistant Lecturer, Department of Geography, Dagon University.
314
process has occurred in last decade and is still increasing. Therefore, it is
necessary to study the migration patterns of Hpa-an Township.
Problem and Objectives of the Research
The main problems of this study could be addressed the following
basic question.
 How and why the people are migrating in Hpa-an Township?
The major objectives of this paper are:
• to study the migration patterns of Hpa-an Township,
• to present the reasons of this migration,
• to observe distance bias and directional bias pattern of Hpa-an
township and
• to assess the changes of occupation structure of migrants of
Hpa-an Township.
Method of Study
Before the study of the migration patterns of Hpa-an Township, about
the migration condition of people in Hpa-an Township were firstly observed
by informal open talks with some local people. Then, the relevant factors for
questionnaires were derived from the pilot observation and these informal
talks. The initial secondary data were collected through different
governmental offices at Hpa-an Town. Depend upon the population
distribution of Hpa-an Township, it was divided into six classes: over 10000
population, between 8000 to 10000, between 6000 to 8000, between 4000 to
6000, between 2000 to 4000 and under 2000 the sample villages were selected
purposively.
In each sample village structured interviews were conducted mainly to
the local people for obtaining the migration patterns of Hpa-an Township.
Random sampling was done on the 10 percent of households in each village
tracts. From the results of obtained data, pull and push factors of migration
and distance bias and directional bias of migration in Hpa-an Township are
analyzed on it. The sampling method of this study is as follow:
315
Table.1. Sampling Methods of the Study
Case
Study
V.T
Name
Pop:
Class
Total
Pop:
Total HH
Sample
HH
1
2
3
4
5
6
Htongaing
>10000
Ein-du
Naung-palain
6000-8000
Mi-kayin
Kawgun
< 2000
7461
40006000
4692
Maingkan
20004000
3400
1105
110 (10%)
687
68 (10%)
436
47 (10%)
214
56
(25%)
16981
800010000
8733
1773
177
(10%)
1471
164
(10%)
*HH = Households
1188
Source: Field Survey in November and December, 2011
Distribution of Sample Villages in this study is shown in figure 1.
Figure.1. Distribution of Sample Villages in Hpa-an Township
Source: Land Record Department, Hpa-an
316
Geographical Accounts on the Study Area
Hpa-an Township is situated in the mid-western part of Kayin State. It
lies between North Latitude 16 º 30' and 17 º 44', East Longitude 97º 21' and
98 º 01'. Hpa-an Township has elongated shape and generally bounded by
Hlaingbwe Township and Kawkareik Township in the east, Paung Township
and Thaton Township and Bilin Township in the west, Kawkareik Township,
Kyeik-ma Yaw Township and Mawlamyine Township in the south and Hpa-pun Township in the north. It has an area of 1120 square miles and comprises
Hpa-an Town proper and 91 village tracts. See in Figure 2.
Figure.2. Study Area of Hpa-an Township in Kayin State
Source: Land Record Department, Hpa- an, Kayin State
317
Migration Patterns of Hp-an Township in 2011
Hpa-an Township is fairly populated. In 1891 and, Hpa-an the
population was over 76,421 persons. Then, it was gradually increasing; total
population was about 308639 in 1983 persons and was increased to 367721 in
1993, continually increased to 388088 persons in 2000 and to 391989 persons
in 2005. In 2011, the total population of Hpa-an Township has reached to
451851 persons. In Hpa-an Township, the density of population over 100
persons per square mile within 1891 to 1964 and there was no much different
on the density of population of Hpa-an Township. Although the total
population increased, the population density decreased to 22 people per square
mile in 1973 because of the expansion of Pyihtaungsu Ward and Aungnan
Ward to combine to Hpa-an Town. From 1983 to 2005 the density of
population of Hpa-an Township hass gradually increased to over 300 persons
per square mile. At present the density of population is 403.4 persons per
square mile in Hpa-an Township. See in Figure.3.
Sr.
1
2
3
4
5
6
7
8
9
10
11
12
13
Year
1891
1901
1911
1921
1931
1962
1973
1983
1993
2000
2005
2010
2011
Population
76421
76591
102490
121692
141068
207000
248362
308639
367721
388088
391989
417913
451851
Density
105
108
102
120
139
184.8
22.8
275.8
328.3
346.5
349.4
373.1
403.4
Figure.3. Total Population and Density of Hpa-an ship from 1891 to 2010
Source: Immigration and Man Power Department, Hpa-an, Kayin State
In the distribution of population in Hpa-an Township, the largest area
in is Hpa-an Town proper with the number of 69392 persons in 2011 which is
the 15 % of the total population of Hpa-an Township. The populated village
tracts of Hpa-an Township are Thar-ma-nya Village Tract (16020 persons or
3.5 %), Hlar-kar Village Tract (12247 persons or 2.7%), Htong-aing Village
(10918 persons and or 2.4 %) of total population in 2012. The least population
318
are found at Pyin-ma-pin-seik Village (1123 person or 0.3 %), Kaw-thin-shu
Village (1166 person or 0.3%) and Kaw-gun Village (1188 persons or 0.3 %)
of total population of Hpa-an Township in 2012. Ethnic group residing in
Hpa-an Township are Kachin, Kayah, Kayin, Chin, Bamar, Mon, Rakhine,
Shan and Pa-O and also others and foreigners. According to the 2011 data,
among the national people who living in Hpa-an Township, Kayin is the
largest population. See in Figure 4.
Figure.4. Ethnic Groups of Hpa-an Township
Source: Land Record Department, Hpa-an, Kayin
The population of a region plays an important role in the social and
economic development of that region. In Hpa-an Township, there are Hpa-an
Town proper and 91 village tracts. In this study, case studies of 6 village tracts
were chosen according to the population distribution and density. Among
them, Htong-aing Village Tract (composed 3 villages) lies in the southern
part, the most populated village tract and Kaw-gun Village Tract is the least
population in Hpa-an Township. Due to the population density, the sample
village tracts were chosen and structured interviews were conducted on 10
percent of total households of each village tract. According to the result of
interview survey, most of the interviewees are Kayin, Mon, Pa-Oh and
Barmar people. Because Hpa-an Township is situated at the Kayin State, most
of the interviewees were Kayin people and other nationality like Mon, Pa-Oh
and Bamar people are also found. Kayin people are mostly found in Naungpa-lain Village Tract and Maing-kan Village Tract. Mon people are found in
Htong-aing Village Tract. See in Figure.5.
319
Figure.5. Nationality of Interviewees from Sample Village Tracts in Hpa-an
Township
Source: Structured Interview Survey, November and December'2011
In this study, nearly all the interviewees in six village tracts are native
people except a few of the people are from near small towns like Thaton,
Hlaing-bwe, Mu-don and Paung migrated to Hpa-an township due to
marriage and settled there. Most of the interviewees are over 31 years age
group, especially 50 and over 60 years age group are significant in this survey.
This situation shows that the young people more migrate than the old one. See
in Figure 6.
Figure.6. Age Structure of Interviewees from Sample Village Tracts in Hpa-an
Township
320
Source: Structured Interview Survey, November and December'2011
As a result of the structured interview survey, all the sample village
tracts in Hpa-an Township take place migration process. Among them,
migration process is more prominent in all sample village tracts. There are
over 50 percent of households in all the sample village tracts in Hpa-an
Township take place migration process. In this case, Kaw-gun Village Tract is
the highest flow of migration occurs with the amount of 69.6% in 2011. See in
Figure 7 and Table 2.
Figure.7. Migration Situation from Sample Village Tracts in Hpa-an
Township in 2011
Source: Structured Interviewees Survey, November and December'2011
Table.2. Sample Households, Migration Situation and Migrants in Hpaan Township
VillageTracts
Sample HH
Migrate
(HH)
NonMigrate(HH)
Migrants
HH= Households
Htongaing
177
99
(55.9%)
78
(44.1%)
202
Ein-du
164
108
(65.9%)
56
(34.1%)
234
Naungpa-lain
110
64
(58.2%)
46
(41.8%)
124
Mikayin
68
39
(57.4%)
29
(42.6%)
99
Maingkan
47
30
(63.8%)
17
(36.2%)
89
Kawgun
56
39
(69.6%)
17
(30.4%)
80
321
Moreover, the numbers of migrants are more than migrated samples
households. It shows that some of the households have more than one migrant.
According to the interview survey, 2 to 5 migrants per household are the
highest percentages in all sample villages in Hpa-an Township. More than 5
migrants per households are also found in this study. See in Figure 8.
Figure.8. Migrants per Households from Sample Village Tracts in Hpa-an
Township
Source: Structured Interviews Survey, November and December'2011
Most of the migrants from six sample village tracts in Hpa-an
Township, the highly flow of migrants people are between 20 to 30 years age
group. The second one is between 31 to 40 years age group in all the sample
village tracts. Therefore, migration process takes place among the adult or
working people in Hpa-an Township. Moreover, in this study, it can be found
that male is more migrating than female within the migrants. See in Figure 9.
Figure.9. Age Structure of Migrants from Sample Village Tracts in Hpa-an
Township
322
Besides, migrant people are mainly in primary education status level in
every village tracts. Some migrants are middle and high education status level
but university and graduate level can be found very few. Therefore, low level
education status is more taking migration than high level education status. See
in Figure 10.
Figure.10. Education Status of Migrants from Sample Village Tracts in Hpaan Township
In this study, migration process takes places in all occupation structure
of local people especially in students and farmer. Furthermore, others
occupation structure of dependency, general workers, sellers, tailor, etc. also
migrate within six sample village tracts in Hpa-an Township. See in Figure 11
and Table 4.
Figure.11. Occupation Status of Migrants from Sample Village Tracts in Hpaan Township
323
Except from Naung-pa-lain village Tract, student is the highest flow
among migrants in all sample village tracts. The second highest flow of
migrants is Farmer. See Table 3.
Table.3. Occupation Status of Migrants in Hpa-an Township in 2011
Occupation
Htongaing
Ein-du
Naungpa-lain
Mikayin
Maing
-kan
Kawgun
Student
47.5%
65.8%
39.5%
66.6%
47.5%
44%
Farmer
21.3%
-
34.5%
32.5%
21.3%
37.8%
Other
21.3%
3.7%
25.1 %
21.3%
21.3%
22.1%
-
20.5%
-
-
-
-
Dependency
Stud= Students, Far = Farmer, Depen= Dependency, Others = sellers, tailor,
general worker, etc.
Based on the results of this survey, there are 11 destinations can be
found among the migrants. In all the sample villages, the highest flow is to
Thailand (especially to Bangkok). The other destinations are Malaysia,
Singapore, Egypt, Australia, Korea, Myawaddi, Yangon, Naypyidaw,
Thandaung, Higyikyun. Over 90% migrants moved to foreign countries,
among them Bangkok is main destination and then follow Malaysia. The other
foreign destinations are very few people as one to 3 migrants only. See in
Figure12.
Figure.12. Destinations of Migrants from Sample Village Tracts in Hpa-an
Township
324
Generally, the migrants go to 11 destinations from six sample villages.
Moreover, the migration took place to other places for a long time and still
increasing. In the following figure show that, the migration took place since
last decade and the highest flow is occurred within 2 to 5 years. See in Figure
13.
Figure.13. Duration of Migration from Six Sample Village Tracts in Hpa-an
Township
Source: Structured Interviews Survey, November and December' 2011
Conclusion, Findings and Suggestions
In order to analyze, a general patterns of migration from 6 selected
sample villages, it can be found that about 97 % of total migrant move out
from their native place and only 3 % of migrants move into Hpa-an Township
mainly from nearby townships (Hlaing-bwe, Paung, Thaton, Mu-don) and
settled there. Therefore it shows that the out- migration is more significant
than the in-migration. Except from a few immigrants into Hpa-an Township,
about 86.3% migrated to Bangkok and 11.1 % migrated to Malaysia. The
other destinations are to Singapore is about 4 persons or 0.5%, to Australia
and Egypt is about 2 persons or 0.2 % respectively, and to Korea is about is 1
person or 0.1 % of total migrants. Moreover, about 5 persons or 0.6 %
migrate to Yangon and Myawaddi, about 2 persons or 0.2 % migrate to
Thandaung and about 1 person migrate to Naypyidaw and Hi-gyi-kyun.
In Hpa-an Township, it can be distinguished into three types of
migrations: rural-urban migration, urban-rural migration, and rural-rural
migration. The most prominent type of migration in Hpa-an Township is
325
rural-urban migration in 2011. Over 96% of total migrants move from rural to
urban which is rural-urban migration. Among them, large-scale flow was to
Bangkok due to job opportunity. Moreover, some of the urban areas from
Yangon, Sittwe, Paung, Thaton, Hlaingbwe, Mudon, and even Hpa-an,
migrants move and settled at villages of Hpa-an Township because of
marriage. Besides, rural-rural migrations are also found in Hpa-an township.
They are also reasons for marriage. In this case, rural-urban migration is the
most prominent when compared with other migration patterns. See in Figure
14.
Figure.14. Migration Patterns of Hpa-an Township in 2011
Distance Bias and Direction Bias in migration of Hpa-an Township
In migration patterns of an area, the distance bias and directional bias
are also apparent. In the migration patterns of Hpa-an township, the distance
bias and direction bias can be found.
Distance Bias: The pattern of migration to a single destination shows the
effects of a distance bias most clearly. In Hpa-an Township, the different
destinations of migrants reflected different distances of migrants.
326
In the case of distance bias of townships, about 1.2 % falls within 200
miles distance range, only 0.5 % falls within 200-400 miles distance range and
about 86.2 % falls within 600-800 miles distance range and about 12.1 % falls
over 1000 miles of distance range. Here, on the following figure show very
clearly the distances of migrants from Hpa-an Township in 2011. The most
noticeable point is that the high percentage of migration occurred within the
range of 400-600 miles from Hpa-an Township and it is represented only one
destination, this is Bangkok. The second highest flow is about 12.1 % which
represent 5 destinations: they are Malaysia, Singapore, Korea, Australia and
Egypt. The rest are very few, only 1.2 % and 0.5%. These destinations are
Yangon, Naypyidaw, Myawaddi, Thandaung and Higyigyikyun. This result
show that the highest flow of migrants are only to Bangkok when compare to
other places. Only one destination of Bangkok is revealed the distance bias
clearly in migration patterns of Hpa-an Township. It shows in Table 4 and
figure 15.
Table. 4. Distances of Migration from Hpa-an Township in 2011
Distance from Hpa-an
Miles
< 200
200-400
400-600
600-800
800-1000
>1000
No. of
area
2
3
0
1
0
5
Migrants
1.2 %
0.5%
0%
86.2%
0%
12.1%
Figure.15. Distances of Migration from Hpa-an Township in 2011
Source: Based on Table 5.
Directional Bias: The directional bias, the greater volume of movement to
some direction when compared to others at similar distances (Integrated
Human Geography). In order to measure directional bias of migration from
327
Hpa-an Township, four directional sectors were divided. These directions are:
(i) North-east Direction,
(ii) North-west Direction,
(iii) South-east Direction and
(iv) South-west Direction
Hpa-an Township is placed at the center. Numbers of migrants for
each sector summed up and measured for percentages. Calculations were
made for all migration patterns found in Hpa-an Township. See in Table 5
and Figure 16.
Table.5. Directions of Migrants from Hpa-an Township in 2011
Sr
No. of Area
Migrants
Direction
North-east
South-east
North-west
South-west
1
5
4
1
0.1%
98.6%
1.2%
0.1%
Figure.16. Directions of Migrants from Hpa-an Township in 2011.
Source: Source: Based on Table 6.
In Hpa-an Township, it is evident that about 98.6 % of total migrants
moved to South-east direction where comprises Bangkok, Malaysia, Australia,
Singapore and Myawaddi. About 1.2 % of migrants move to North-west
direction (Egypt, Naypyidaw, Yangon, Thandaung), about 0.1 % moved to
328
South-west and North-east Direction, Korea and Higyikyun. In this case,
South-east direction of out migration flows is the greatest flow among the
migration flow. As above mentioned patterns, it is significantly revealed the
directional bias in the migration of Hpa-an Township.
Pull Factors and Push Factors of Migration of Hpa-an Township
The presumed positive attractions of the migration destination are
known as pull factors and negative home conditions that impel the decisions
to migrate are called push factor.
Pull Factors: Nearly all of the migrants from six samples village tracts had
moved into other places for mainly reason are job opportunity. Among them 2
persons moved to Australia, 2 persons moved to Egypt and 1 person moved to
Bangkok are reasons for education. One main reason for migration is a
migrant firstly go to the new land and give some information to the native
land or when he/she visit his village, he/she inform another person who want
to move to Bangkok. Therefore, this migration is based on the job opportunity
from the information of first migrant. In the second case, first migrant moved
to Bangkok and for job opportunity and then money send back to the country
of origin to pay fare of those wishing to follow the other migrants in the same
routs. Another case, earlier migrants to newer comers of their friends, relatives
and neighbors, and the migrant serves to relay information back home from
social network. In this process showed that kinship and friendship ties make
the chain migration in Hpa-an Township. The other reason for high flow to
Bangkok is easy to get more money than native land. Very few migrants are
due to environmental attraction.
Push Factors: All the migrants from six sample villages of Hpa-an Township,
the main reason is lack of professional job opportunity. There is no
professional job in their native land, the people migrate to other area,
especially to Bangkok, where has more job opportunity. The second group of
migrants is when they lost their farm land due to climate change, they choose
to migrate. Agriculture makes them always in debt so that they migrate to
search another job. Difficulties of getting job are one of the main reasons of
migration of this area that are impact to the family or for livelihood of the
local people. Political instability is other main factor that creates the negative
impact of social and economic situation. Among them difficulties or loss of
job, lack of professional job opportunity is the main reasons for migration
from this area. See in Table 6.
329
Table.6. Reasons for Migration in Hpa-an Township in 2011
Sr
Pull Factors
Sr.
Reasons
Push Factors
Reasons
1
job opportunity (over 90%)
1
difficulties or loss of job
2
education opportunity (0.6%)
2
3
environmental attraction
3
lack of professional
opportunity
4
kinship and friendship ties
4
5
money sent back to the country
of origin to pay the fare of those
wishing to follow the same
migration route
5
6
6
job
for livelihood
for family
no profit in agriculture
instability of local area
easy to get more money than
native land
Changing Occupation Patterns of Migration in Hpa-an Township
Occupation patterns of migrants reflected the changes in their
occupational structure mostly in the case of students. Second one is farmer
and the others are dependency, general workers, sellers, tailor, taxi driver,
government services, etc. In this case, changes of occupation of male and
female are different. For male, student changes their occupation are factory
worker, restaurant, manufacturing, industry, and workshop are prominent.
Farmers are to be factory worker, construction and general workers. Similarly,
general workers, sellers, dependency, government service are also changed
their occupation. See in Table 8.
For female, changes of occupations are students to domestic help,
seller, restaurant, factory, etc. Among them, only three persons are changed to
students. The others are agriculture, seller, dependency and tailor also
changed their occupation respectively.
In this case, it is significant that males are changing to factory is
prominent in every occupations structure and female is to domestic help is
significant in changes of occupation structure. It can be shown in Table 7.
330
Table.7. Changes of Occupation Structure of Migrants in Hpa-an Township in
2011
Occupation (Male)
Before
Students
Occupation (Female)
After
Before
After
Factory, restaurant,
student
manufacturing,
seller, general
worker, sale clerk, ,
furniture, industry,
workshop, petroleum
station, construction
domestic help, seller,
Farmer
Factory,
construction, seller,
restaurant, general
worker
agriculture
domestic help,
general worker,
factory, restaurant,
seller,
dependency
driver, seller, factory
seller
domestic help,
factory, seller
sellers
factory, seller
tailor
domestic help, seller
general
Worker
factory, general
worker
dependency
domestic help
government
Service
factory
other
domestic help
others
factory,
worker
restaurants, factory,
industry, student,
manufacturing,
general
Source: Structured Interviews Survey, November and December' 2012
Findings and Suggestions
According to a general pattern of migration from 6 selected sample
villages, all these villages have more migrant people than non migration
people. In this case, migrants are adults most of them are between ages of 18
to 45 years. Moreover, out migration is very apparent in Hpa-an township
since last decade and still continuation. Migration from the Hpa-an Township
is moved to the proximity of abroad mainly to Thailand (Bangkok). Therefore,
Bangkok is the major destination of migrants from Hpa-an Township with the
331
amounted about 86.2 % of total migrants. Therefore, it shows that ruralurban migration.
In Hpa-an township, one of the migration influencing factors is social
network that links earlier migrants to newer comers of their friends, relatives
and neighbors, and the migrants serves to relay information back home from
social network. As one of the family members go to a place, there is a grater
connection to an area and a greater potential of numbers of migrants are
follow them. Thus, it can be found that there are one or more migrants per
only one household. Most migrants are adult persons, between 20 to 40 years
age group, are strongly concerned with job-related movement, which is
mainly reasons for movement in this study. As a result from survey, there are
many people who came back from Bangkok and some people are still going to
there, but they will come back their native land when they want to return.
Therefore, that can be also regarded as labor mobility. Migration for
economic and social reasons is a continuous process, like these situations are
significant in migration of Hpa-an Township. Most of the migrants follow to
earlier migrants who have previously migrated, so that migrants from a
particular area of origin move to only one destination in the same route. The
other migrants often involve money being sent back to the country of origin to
pay the fare of those wanting to follow the same migration route. This process
is continuous in Hpa-an Township and create chain migration.
Finally, there are some suggestions which based on the results from
this surveying: it is necessary to promote the agriculture activities by using
new technology because among the migrant people, the second highest group
is farmer in all sample village tracts and who have difficulty in their job and
earned no profit in agriculture. Then, it also needed to create the better job
opportunity to the local people because most migrants took place migration
for mainly reasons for job opportunity and lack of professional job in this
area. And it is strongly recommend to develop every sectors in this area
especially in education sector.
Acknowledgement
We are greatly indebted to Sayagyi U Hla Htun Aung (E.C member, Myanmar
Academy Arts and Science) for his encouraging advice and guidance of this paper. We would
like to express our grateful thank to Dr. Saw Pyone Naing, Pro Rector, Mandalay University,
for his guidance and valuable advice for this study. Finally, we deeply heartfelt thanks to our
colleagues and our students (Second Year Geography in 2011 intake batch, Hpa-an
University) for their eagerly and willingly help and supports when fieldwork to obtain the
collecting data.
332
References
Fellmann,J.,Getis, A., Getis, J. (1990) : Human Geography: Landscapes of Human
Activities.(3rd Ed.) WCB. Wm.c Brown Publishers,U.S.
Longman (1992): A Dictionary of Basic Geography: Human & Physical. (2nd Ed) Butler &
Tanner Ltd. Great Britain
May Thu Naing (2007): Effects of Rural -Urban Migration on Immigration into Mandalay.
Unpublished, PhD Dissertation, Mandalay University.
Sustainable Development of Floating Garden Cultivation in
Inlay (Inle)
Nilar Aung1 and Associates2
Abstract
Inlay Lake is the most important lake and second largest lake in Myanmar
because of its economic, social, cultural and ecological implication. In
relation to physical features of Inlay Lake, there are variation in spatial
patterns and seasonal changes in economic activities especially in
agricultural activity. Because of the limited spaces for agricultural lands,
unique types of cultivation, known as floating garden cultivation, is
common in this area. Floating garden cultivation is a successful traditional
method and practice of Inlay people (Intha) and a unique character of Inlay
Lake. Inlay Lake is suffering from environmental effects due to increased
population. In last decade, the lake has been facing with combined threats
due to natural and manmade pressure which is a cause of decreasing both
water and environmental quality, such as water quality, water holding
capacity, disturbance in the water flow and decline in population of fish and
other aquatic life. Moreover, large scale deforestation and shifting
cultivation practice in the surrounding areas are severely threatening the
environmental stability of the entire water shelf area of Inlay Lake.
Sustainable agriculture is "a way of practicing agriculture which seeks to
optimize skills and technology to achieve long-term stability of the
agricultural enterprise, environmental protection, and consumer
safety."(www.sustainabletable.org). The purpose of this paper is to reveal
the present situation in facing the environmental degradation in Inlay Lake
and to maintain floating garden cultivation without decreasing its cultural
and environmental values.
Key words: sustainable agriculture, floating garden
environmental degradation, water pollution
cultivation,
Introduction
Inlay Lake is a vital ecosystem and economy of Shan State, providing
many goods and services to the surrounding communities. The services
include a major tourist attraction, providing agricultural products, traditional
products and are a habitat for rich biodiversity and traditional culture. During
the 1990s, the effect of climate change and variability in the forms of drought
and flood has occurred throughout the country. In recent years, the changes in
the climate have been characterized by changing rainfall patterns, increasing
1. Associate Professor, Department of Geography, Hinthada University.
2. Third year & First year (Honours) Students, Department of Geography, Hinthada
University.
334
temperatures. Inlay Lake is one such area in the country that is facing the
devastating effects of climate change as well as unsustainable natural resource
use practices. Many other factors contributing to this, including deforestation
in the watershed area, eutrophication, heavy sedimentation, overuse of
chemical fertilizers and insecticides and reduction in the water surface area of
the lake. Degradation of Inlay Lake imposes major economic and social losses
to the area. These include decreased agricultural production and fish catch and
effect on the health of the local community.
Figure (1) Conceptual Frame Work
Therefore, appropriate conservation and management of the Lake is
essential to enable Inlay lake ecosystems to survive and continue in providing
important goods and services to the local and national community.
Based on figure (1), both positive and negative impacts can be
observed. Therefore sustainability of floating garden cultivation in Inlay Lake
requires justification between these positive and negative impacts on the local
lake environment. It is necessary to change from the negative impact to
positive impact between floating garden cultivation and economic, social and
environmental values of Inlay lake area. The main aim of this paper is to study
335
the present conditions of floating garden cultivation and major influencing
factors for environmental deterioration of Inlay Lake area.
Methodology and Data Sources
This paper mainly focused on field observation at Kela village in 2012
which is involved in floating garden cultivation practices. Due to time
limitation only one sample village was selected. Therefore convenience
sampling was undertaken with farmers, business men, and other persons from
Non Government Organization were taken. Intensive interviews were
conducted to the 15 farmers from Kela village (the highest percentage of
floating garden cultivation practising within Inlay Lake Area), to examine the
present status of floating garden cultivation. During the field observation, the
data concerning images of local peoples on lake environment were also
collected from 10 business men, (including weaving industry, gold and
silversmiths, blacksmiths, painting, handicrafts shops), some person from
organic based companies who are involved in introducing good agricultural
practise in Inlay Lake area and local authorities.
Research Questions
What are the major causes for environmental deterioration of Inlay Lake area?
Why is the floating garden intensive cultivation?
Objectives
1. to examine impacts of floating garden cultivation on Inlay Lake
environment
2. to give suggestions on sustainable development of floating cultivation
The Study Area
The study area is located between North latitude 20º27 ' and 20º36' and East
longitudes 96º 53 ' and 96º56', situated in Southern Shan State. The Inlay Lake
is solution lake develop original tectonic lake. The actual open area is now
only 14.48 km (9 miles) from north and south and 5.63 Km (3. 5 miles) in
width from east to west. The water surface area is 150 square kilometer (57.9
square miles) in rain season and 100 square Kilometer (38.6 square miles) in
dry season (Mu Mu Than). The altitude of Inlay Lake is 888 m (2915 feet)
above sea level. The Inlay Lake is surrounded by mountain ranges on the
eastern and western banks of the lake in north - south alignment .Dry farming
and shifting cultivation are found on these ranges. The large scale
336
deforestation and shifting cultivation practice in the surrounding areas are
threatening severely the environmental stability of entire water shelf area of
Inlay Lake. There are 29 streams in Inlay Lake. Among these Nnamlat stream,
Yebe stream, Thandaung stream and Indine stream are important streams and
they have largest catchment area in Inlay Lake.
Climate
In the hot season, the heat is oppressive and midday temperatures of over 100º
F are not unusual in the month of April, although the average temperature for
the month is between 80º F and 90º F over the lake itself. During the rainy
season temperatures are brought down lower like other parts of Myanmar. In
December, the minimum temperature is about 40ºF. The maximum may rise
to 85º F in April. The rainy season begins about the end of April or the
beginning of May. Rainfalls are continuously and heavily after June and
August which are the wettest months.
Vegetation
Much of the original forest cover the ridges has been removed and replaced by
grass. In ancient time, the ridges on the west and east, facing the lake seemed
to have been covered with deciduous trees with an undergrowth of shrubs,
herbaceous plants, ferns, mosses, lichens etc. Direct cause of deforestation
depends on factors such as the expansion of shifting cultivation, livestock
production and fuel wood harvesting, transformation of forest area into
permanent crop lands and so on. Due to shifting cultivation practiced by
farmers this vegetation has disappeared. The lake is surrounded by swamp
vegetation on all sides. Reeds and tall grasses are found northern, western, and
southern end of the lake. Originally, they appeared to be well encroached to
the land covered by shallow water around the edge of lake.
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Figure (2) Location of Inlay Lake Area
Soils
The soils of the Lake could be classed as alluvial soils. However, certain
interesting distinctions appear among the soils of various parts of the lake
plain. On the north of lake plain display the deep rich brown recently
deposited alluvium. The eastern side of the lake exhibits deep blackish clayey
alluvium. The soils of the region play a great role in determining the crops
grown in the area. There are five main types of agriculture in Inlay Lake. The
patterns of agriculture reflect the physiography and soils. These are paddy
cultivation, floating gardens, taungya or shifting cultivation, dry farming or
ya cultivation, agriculture in the lake margin such as gardens on the land area.
Population and ethnic groups
People have been residing in the Inlay region since time immemorial owing to
its favorable condition for civilization. The population in and around Inle
Lake has been growing steadily over the past 25 years. There are 35 village
tracts consisting about 21,550 households with a population of in 153,678 in
2006-07.and consisting about 30,000 households with a population of in
154,092 in 2011 and 162,371 in 2012. The ethnic groups of Pa-O, Danu,
Taungyo, Intha, Shan and Bamar reside in the Inlay lake area and among them
Intha is the major ethnic group. The majority of the people are Buddhists.
338
Inthas posses a unique culture of rowing boat by leg and growing vegetables
on floating farms therefore floating agriculture is a major land use in this area.
Types of Economic Activities
The most important type of activities is various types of agriculture. Other
economic activities include small-scale fishing, animal husbandry, cottage
industries of various forms and commercial activities.
Although tourism has been found in Inlay Lake for many years, tourist
industry is rapidly growing economic activity with the consequences of the
transformation of economic and political system in the country. The most
important and famous cottage industries are silk and cotton weaving, gold and
silversmiths, blacksmith of iron works. The main occupation of the people of
Inlay Lake area is agriculture.
Environmental Conditions of Inlay Lake Area
According to figure (4), during 1993-1998, Inlay-region faced with
environmental degradation as drought problem in which annual rainfall
intensity is very low. In 1997-1998, annual rainfall intensity of Inlay is less
than 600 mm. Due to increase in population, Inlay Lake is suffering the
environmental effect within last decade. Large scale deforestation and shifting
cultivation practice are other major problems that can be threatening severely
the environmental suitability of entire the watershed area.
Fig. 4 Annual rainfall and rain day totals for a 17-year period at Inle Lake
Source: Roy C. Sidle, Alan D. Ziegler, and John B. Vogler: (2006),(data from Khaing Wah
Wah Maw, Integrated Community Development Project, Inle Lake)
Moreover, deforestation and more intensive agriculture on its western and
northern the watershed areas have brought in increasing amount of silts and
nutrients into the shallow lake. Furthermore, construction of houses in Inlay
339
Lake consumes a large amount of timber twice as much as in ordinary
construction of houses on the land. According to last ten years records from
Irrigation Department, the lake bed was silted up to about two meters within
this duration (Mu Mu Than 2008). One of the major causes for deforestation is
fuel wood utilization of local people. “About 90 percent of the villagers within
the lake area and all fuel wood needed come from nearby forest” (Saw Pyone
Naying, 2007).
As a consequence, sedimentation has been seriously affecting the surface area
of lake which has shrunk. In the rainy season, turbidity rate was very high in
the mouth of streams especially in western part of Lake. Concerning the water
quality,“ The assessment of water quality results show that some of water
quality variables such as conductivity, COD and total Coliform were beyond
the limit of WHO drinking water quality standard”(Saw Yu May,2007).
Moreover, according to figure (5), more than 90 percent of respondents
mentioned that major causes of water pollution come from floating garden
cultivation and disposing all domestic waste, and oil spill from boats into the
lake. However, most of business men mentioned that they disposed their
waste at disposal sites. Thus floating garden is major source of water pollution
in Inlay Lake area.
Figure (5) Reasons for water population
Source: field observation 2012
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Floating garden cultivation
Local people of the Inlay Lake use the land areas as much possible as they can
because of physical conditions. “Floating garden was founded by U Pho Lone
of Pwesargone in April 1907. He cut off strip of Virgin Island and alluvium
soils are put over the strip measuring 7.6 meter (24 feet). He then grew
tomatoes and chilies that thrived successfully. Then, U Pho Che from Lin kin
village also made an experiment of floating garden, which was 30 feet long,
and he was also successful. In 1958 tomatoes, vegetables, chilies and also
cucumbers were grown in Inchan Kela village, which became one of the
villages those posses the highest acreage of floating gardens. Floating garden
cultivation is successful traditional methods and practices of the Intha peoples.
Floating islands are formed from coarse grasses, reeds, sedges and other
aquatic vegetation. The dead parts of aquatic and marsh plants become
entangled together and are bounded by bog mosses and algae into expanses of
fen which float freely. The remainders of the decaying aerial portion are burnt.
Black silt from the bottom of the lake is carried by flat boats and spread over
it to the extent the bed is not sunk but still floating. Then floating islands are
towed into position and anchored with bamboo poles. The floating islands
thus, become a growing medium for planting fruits, flowers, vegetables, and
other cash crops from which a lot of income is derived by the Inthas (Ko Ko,
2009).
The floating island can be used up to about 15 years or as long as submerged
mattress can hold its buoyancy. The sunken mass of decayed material has to
be taken out of the lake bottom and put back on the land. However, the
practice of farming on floating cultivation also diminishes the area of the lake.
At the villages in the flooded areas, the cultivation is done twice in the rainy
season and in the cool season but at the villages in the shallow shoreline, only
once in the rainy season. The floating garden can be used from ten to fifteen
years. At the present, floating garden is intensive type of cultivation among
the various types of agriculture in Inlay Lake area.
Major driving forces to intensive cultivation
Floating garden cultivation is a major economic activity of Inlay Lake.
Increasing numbers of population and restriction on expansion of newly
farms, increasing demand of growing item and profits, highly reliance on
seeds companies are major driving forces to intensive cultivation.
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Figure (6) Population of Inlay Lake Area in 2006-2007, 2010-11 and 20102011
Sources: Immigration and National Registration Department, Taunggyi
According to figure (6) the population of Inlay Lake increased from 153,678
in 2006-07 to 154,092 in 2010-11 and 162,371 in September 2012. According
to figure (7 & 8), the total cultivated area of floating garden was in 599.208
hectares (1488.13 acres) and 831.62 hectares (2055.71 acres) and 800.811
hectares (1977.3 acres) in 1997-98, 2006-07 and 2010-11 respectively. There
are 20 village tracts which are involved in floating garden cultivation. The
most important growing village tracts are Min Chaung, Kela, Ngaphe Chaung,
Nanthe, Thapyaypin, Thale Oo and Mine Thauk. In relation to the population
growth of Inlay Lake area, the increased numbers of farmer and floating
garden cultivation areas were encountered because the majority of people in
Inlay lake area are involved in floating garden cultivation.
342
Figure (7) Floating garden acreage of Inlay Lake Area in 1997-98, 2006-2007
and 2010-2011
Sources: Land records department, Nyaung Shwe
The emergence of newly floating farms was restricted in recent years.
Consequently, the results of man- land ratios decreased slightly from 1:0.44,
1:0.42 and 1:0.4 in 1997-98, 2006-07 and 2010-11 respectively. Thus, it can
cause intensive cultivation to the floating garden. In 2009, the profits gain
from (1) acre of floating garden was from (60,000) kyat to (100,000) kyat. It
can be distributed for goods of the living of native people. (Ko Ko, 2009). In
2012, farmer who own 1 acre of floating garden from Kela village, received
about 10, 00,000 kyat per year. (It may be due to inflation.) However, the
increased in profits is also driving force for intensive cultivation.
Tomato is the main crop on the floating garden and sent to the major cities.
During the rainy season, tomatoes are sent to Yangon, Mandalay and other
major cities within Myanmar, while lowland areas cannot be used to grow it in
this season. Other crops are eggplants, chilies, cabbage, cauliflowers,
cucumbers, flowers, etc.
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Figure (8) Numbers of farmer in 1997-98, 2006-2007 and 2010-11
Source: Immigration and National Registration Department, Taunggyi
Tomato is the most profitable crops. However, it also depends on market price
conditions of tomato at Yangon, Mandalay and other cities. Therefore, when
the tomatoes price was higher in Yangon, Mandalay and other markets,
farmers used more fertilizers and pesticide in their floating farms to get more
profits from them. Chemical fertilizers and pesticides used in floating garden
can have an effect on the lake environment. Thus, the water pollution is
severely caused by pesticides and fertilizers from the floating tomato gardens.
Previously, farmers used to rely on natural fertilizers. With advance of
technology and hybrid seeds more extensive use of chemical fertilizers for
increasing the agricultural products was seen.
Thus, the function of Seeds Company is also major driving force for intensive
cultivation. By studying figure (9), most of the farmers in floating garden
cultivation are being provided by seeds companies or agents through
wholesalers and retailers and then farmers have to repay back the total cost
for seeds, fertilizers and pesticides to company after the selling their products.
Therefore, most of the farmers rely on Seeds Company for availability of
seeds and other requirements.
344
COMPANY
BRANCH
AGENT
TOWN
WHOLESAER
VILLAGE
WHOLESALER
RETAILER
FARMER
Figure (9) Distribution network of seeds, chemical fertilizers and pesticides
Source: Based on Saw Pyone Naying 2007
According to field results, the farmers have less chance to control the amount
of growing acreage themselves. The intensive cultivation of floating gardens
may lead to the use of more fertilizers and pesticides which can effect on
negative effect to the lake water and aquatic life.
Environmental awareness of local peoples
The lake is the home of about 160,000 people, many from the native Intha
group who have lived along its shore for centuries. “The most recent statistics
show that population concentration is 95 people per square km around the lake
and 398 people per square km on the water” (Mu Mu Than). Local people also
noticed changes in flora and fauna in relation to their physical conditions.
They can compare previous flora and fauna to recent one. According to their
images, several plants and animals disappeared.
“About 68 percent of the respondents mentioned that they realized
environmental conditions have changed in Inlay Lake"(Saw Pyone Naying,
2007). And then, compared to field results in 2012, about 97 percent of the
peoples who are involved in floating garden cultivation as well as other
business men mentioned that their environmental conditions have been
345
changed since last 10 years. The direct comparisons between these two results
are inappropriate (the basic facts of sample areas and sizes are not exactly the
same). However, we can generally assume that almost all of local peoples
accepted that their environmental conditions are being deteriorated.
Inhabitants of the Inlay Lake have been using the water from the lake as their
sole sources for domestic water supply and at the same time disposing all their
domestic waste into the lake without encountering extensive health hazard for
decades. And then most of the latrines are still directly discharge into the open
body of water. This fact, combined with increase in population and disposal of
all human wastes into the lake have began to exert a general strain on the
assimilation capacity of the lake water. At the present time, the inhabitants
have begun to use rain water by constructions of rainwater collecting tanks, It
is clear that majority of peoples in Inlay area, accepted that lake water is not
suitable for drinking and cooking.
According to field results, 95 percent of respondents mentioned that now they
couldn't use lake water for drinking and they got water for their home usage
from Nyaungwin village.
Concerning waste disposal, 85 percent of respondents revealed that they
collected and burnt their rubbish at other place on the land which is located
out of village, however some mentioned that there are no systematic
dumpsites and still they practise outside dumping. Moreover, local peoples
also realized that residual effect of various chemical fertilizers and pesticides
is also hazardous for people's health. The participation of local peoples and all
visitors are very important disseminate direct disposal of solid waste for
protection of water contamination.
According to field observation result, 97 percent of respondents, mentioned
now they perceived that their homeland is being faced with some problems
and which tend to environmental deterioration.
Conclusion and Suggestions
Inlay Lake is famous for its natural beauty and unique culture as national
treasure. Inlay Lake is also important from economic points of view in the
country because it has long been famous for pleasant climate, attractive
landscape and unique lifestyle and handicrafts thus making it a prime tourist
resort. Floating garden is one of the unique characteristics of Inlay Lake and
famous pagoda festivals. And also Inlay Lake is an important natural resource
of Myanmar, because it is the original source of Baluchaung which is the only
346
outlet of the lake connected to Mobye Hydro-power reservoir. The custom and
culture of its ethnic people especially the famous Inlay lake leg rowers are
world renowned. The lake is home to the Intha people, who have developed a
unique way of living style in the country.
Intha possess a unique culture of rowing boat by leg, growing vegetables on
floating farm and floating markets. The majority of peoples are involved in
floating garden cultivation. The floating gardening cultivation play a vital role
balancing between social, economic, cultural and environmental value of
Inlay Lake area. Floating garden becomes more intensive cultivation because
of population growth and increasing demand for its products. Consequently,
economic value will increase and that can give positive impacts to social value
where as it can also give negative impacts to cultural and environmental value
of Inlay Lake.
In relation to our field results in 2012, almost all of local peoples in Inlay
perceived their environmental deterioration especially farmers from floating
gardens. They all accept the major sources of water pollution come from their
farm sites. There is need to adopt the suitable agricultural practise for
sustainable development of floating garden cultivation in Inlay Lake.
The best way for sustainable agriculture is to use organic fertilizers and
pesticides in cultivation and to avoid chemical fertilizer and pesticides. At
present time, Dear Myanmar Company introduced to GAP (good agriculture
practices) which can reduce the negative impacts on environmental value and
social value of lake by using only natural fertilizers. Farmers organized as
Organic Farmers Groups including ten members and from which each of the
members continue to attract other farmers to participate in Organic Farming
Groups. In our field survey, there are 10 groups in Kela Village. During the
field survey, most of farmers from Kela, used to grow with three types of
cultivation (pure organic, mixed with chemical and pure chemical). Organic
companies distribute some tomatoes seeds (Kyauk Ni) and organic fertilizers
and pesticides. Furthermore, the products from organic farm are bought by
Dear Myanmar and other companies at the same price with non-organic
products .Therefore, organic farmers can get the same profits compared with
other non-organic farmers. Furthermore, the total costs of organic farmers are
less than non-organic farmers. According to figure (10) there are (98,200
kyats) differences on total costs between organic and chemical farms.
347
Sr.
Items
Amount
1.
15:15:15
2 bags
36000
Total
cost
(Kyat)
90,000
2.
25:7:7
2 bags
385000
77,000
3.
Pesticides
24 bottles
200000
200000
Price
(Kyat)
Sr.
Items
Amount
Price
(Kyat)
Total
cost
(Kyat)
1.
6 bags
15000
90000
2.
Zwe
Myanmar
Ywet Sein
24 bottles
2700
64800
3.
Ze wa
24 bottles
4000
(Chemical Fertilizer)
96000
250,800
349,000
(Organic Fertilizer)
Figure ( 10 ) Differences of total costs between chemical and organic farms
* based on .1 acre of floating garden (Shan Maw Myay)
According to survey results, 90 percent of farmers like to use natural fertilizer
but they have not totally accepted yet on organic pesticides. Now, farmers
from floating garden cultivation started to use pure organic, mixed with
organic and chemical fertilizer and pure chemical fertilizer. Majority of
farmers prefer to use mixed with organic fertilizer and chemical pesticides It
cannot be easy to bring about sudden change in agriculture practises but local
people should learn to make sure that Inlay must be in good hands for the sake
of future generation and their participations is vital role in working
environmental conservation of Inlay Lake area. The public awareness and
education are important concerning the proper use and small scale control of
chemical fertilizers and pesticides for cultivation. According to field survey,
the market for organic product is being planned to open at Yangon and
Mandalay Cities by Dear Myanmar and will sell these products. By doing so,
the new organic marketing channel will appear and farmers will follow this
channel practicing the good agriculture practices.
To reduce the negative impact to environment, it is necessary to create other
alternative economic activities for local peoples such as creation of jobs
opportunities in tourist industry. “Amongst the many impacts that tourism
may exert upon host areas, the processes of physical and economic
development are perhaps the most conspicuous. These effects may be evident
in physical development of tourism infrastructure such as accommodation,
retailing, entertainment, attraction, transportation services, etc); the associated
creation of employment within tourist industry; less visibly, a range of
potential impact upon GDP, balance of trade and the capacities of national or
regional economies to attract inward investment”.( StephenWillian, 1998, p
348
69,). At the moment, the consideration should be done changing from the
commercial orientation on agriculture to tourism industry which can create
more job opportunities for local peoples without giving negative impacts on
lake environments. Moreover, it will also lead to rely less on agriculture. As a
final point, to maintain long-term existences of floating garden cultivation, it
is responsibility of all local people living in and out of the lake area and also
all Myanmar nationality and, to all who love Inlay and its traditions. The
protection and conservation of sustainable development of Inlay Lake is also
extremely important.
In addition, the establishment of a cultural and natural sound environment in
Inlay Lake needs collaboration and cooperation of local people activities,
contribution of their knowledge and their intensive support is very important.
Anyway, more extensive studies are needed because the lake is thought to be
the most changing site in country as a result of both the booming tourism and
agricultural activities.
Acknowledgement
I would like to show many thanks to Dr. Nay Win Oo, Professor & Head of the Department,
Hinthada University, for allowing this paper. I also wish to acknowledge their deep gratitude
to third year and first year (Honours) students who participated in the field observation to
Inlay Lake in 2012. And then, I owe to many peoples, especially to key informants. Without
their cooperation, this study will be impossible. Special thanks to U San Win (Kela), U Than
Htun Aung (Dear Myanmar) and U Soe Win.
References
Hla Tun Aung (2003): Myanmar: The Study of Processes and Patterns, NCHRD, University
press, Yangon.
Ko Ko (2009): The geographic analysis of floating garden cultivation in Inlay Lake, research
paper, Department of Geography, Taunggyi University.
Mu Mu Than (2008): Community Activities Contribution to Water Environment Conservation
of Inlay Lake, Irrigation Department, Yangon, Myanmar.
Roy C. Sidle, Alan D. Ziegler, and John B. Vogler: (2006) Contemporary Changes in Open
Water Surface Area of Lake Inle, Myanmar, Integrated Research System for
Sustainability Science and Springer 2007 http://www.environmentalexpert.com
Saw Pyone Naying (2007): Environmental Images and Indigenous Conservation Methods of
Rural People in Inlay lake, research paper, research project, University of
Yangon.
349
Saw Yu May (2007): Changes of Water Quality and Water Surface Area in Inlay Lake: Facts
and Perceptions, Unpublished PhD Dissertation, Department of
Geography, University of Yangon.
Stephen Williams (1998): Tourism Geography, Routledge, New Fetters Lane, London.
Geographical Assessment on Settlement Patterns in Maubin
District, Ayeyarwady Region
Khin Khin Han1, Khin Khin Htay2, Kyaw Khing Win3
Abstract
This study attempts to provide the spatial analysis of settlement patterns in
Maubin District, Ayeyarwady Region. This district has an area of 4277.339
sq-km and more than one million people. Although the majority of the
expanding population continues to live in rural areas, urbanization
processes have progressively developed in the district. Topographic Maps
(1954) and (2010) are used in conjunction with the Geographic Information
Systems (GIS) and Remote Sensing (RS) to investigate the expansion of
settlement. Moreover, Autocorrelation is used to investigate the estimated
origin of village by using the village centroids as dependent variables and
water bodies, rivers and streams and road as independent variables for the
analysis. The target of the value at (0.00) level to explain the variability in
the village settlement distribution was applied. From the above result
estimated origin of village shows a close relationship with water bodies,
rivers and streams. Besides, A Multiple-Nuclei Model is applied to explore
spatial distribution pattern of town settlement in the study area.
Introduction
Since the beginning of human history, man has lived in groups, big or
small, settling all over the surface of the earth. Man began to settle at a place,
where suitable residential ground, drinking water sources and arable land are
found. These grew into a considerable size in number. So, man chooses good
geographical bases for his settlement. These geographical bases are in a state
of constant change, both in time and place. These are diverse and various even
in a given region. Settlements of different regions with diverse characteristics
create various types and patterns. Rural settlement is generally described by
several factors. It is generally described either dispersed or clustered but to
what extent is it dispersed or clustered is the phenomena that make up the
pattern.
Study Area
Maubin District is located in Ayeyarwady Region, Myanmar. It has an
area of 4277.339 square kilometers (1651.49 square mile). The study area is
1. Dr., Associate Professor,Dr., Department of Geography,Yangon University of Distance
Education
2. Dr., Lecturer, Dr., Department of Geography,Yangon Institute of Education
3. Dr., Lecturer, Dr., Department of Geography,Magway University
352
located latitudinally between 16° 31' and 17° 25' north and longitudinally
between 95°15' and 95° 55' east. The study area is composed of four
townships. It is bordered by Zalun Township in the north, Taikkyi Township
in the northeast, Htantabin Township in the east, Kyaiklat Township in the
south, Twantay in the southeast, Kyaunggon Township in the west and
Kyonepyaw Township in the North West (Figure 1).
Aim and objectives
This analysis is conducted with an aim and three objectives:
Aim
1. To analyze the spatial and temporal changes of settlement patterns
in Maubin District.
Objectives
1. To study spatial distribution of population pattern and land use
pattern,
2. To assess how villages have originated,
3. To learn about town patterns,
4. To examine the social and economic activities that are related to
those settlement patterns.
353
Sources of Data and Methodology
Field survey and secondary data are derived from official statistics,
orthophoto, satellite images and one inch maps (No. 85-O 8, 7, 8, 11, 12, 16
and 85-P 5, 6, 9, 10, 13, 14), UTM1: 50000 scale maps (1695-1, 1695-5,
1695-6, ,1695-9, 1695-10, 1695-13, 1695-14 and 1795-4, 1795-7, 1795-8,
1795-11, 1795-12, 1795-16), mapping data linkage and analysis were done by
Geographic Information Systems (GIS) and Remote Sensing technique (RS),
with the help of topographic maps, orthophoto, satellite images (30 meter
resolution) and Google satellite images. Database as areas of village tracts and
villages are shown as polygon, location of village centres as centroid, road
network as line, rivers, streams and water bodies as lines and polygons and
Digital Elevation Model (DEM) are used for this analysis.
Spatial and Temporal Changes of Settlement Patterns in Maubin District
Expansion of Settlement
In the study area, Topographic Maps (1954) and (2010) and Aerial
Photographs and Google Imageries are used to investigate the expansion of
settlement.
The Settlement Patterns on Topographic Maps in1954and 2010
The Topographic Maps (1954) shows the road network appeared
distinctly with very few metal roads found near towns of Pantanaw, Maubin,
Danubyu and Nyaungdon. In the study area, most of the cart roads are parallel
along the rivers and stream. It is noted that public transportation had been
diverted from waterways to land. The settlement pattern shows the
communities are clustered along rivers and streams with expansion towards
the rivers and stream shown as ribbon development.
The Topographic Maps (2010) shows settlement expanded and
scattered along the branches of main roads along the Yangon- Pathein road,
Yangon-Maubin-Bogalay road, Maubin- Mawlamyingkyun and PantanawDanubyu roads and appeared as nearly a square shape. It can be explained that
public transportation was developed and connected the some village roads.
The community was expanded not only along the rivers and streams but also
expanded along the transportation network. The transportation expansion is
useful for infrastructure development in the community.
354
At present, the transportation is more convenient and the continuous
transportation network developments make the settlement more dense with
and expanding community. The settlement shows a cluster pattern at
intersection of roads and began to scatter along the roads and waterways as
ribbon development or linear pattern development. It is noted that, during
1954 -2010 there were changes in town area as well as village areas. In 1954,
town and village areas were calculated 157.93 square kilometers (60.97 square
miles) and 209.41 square kilometers (80.85 square miles) were found in 2010.
It was mainly due to the expansion of transportation, both road and waterway.
Therefore, a rapid change in basic transportation makes a rapid expansion in
the settlement patterns in Figure 2.
Sukawattanavijit.C. investigated the relationship between land use,
infrastructure network system, population distribution and settlement pattern
in Nakhon Pak Kret municipalities (Thailand) from 1996- 2006 and it
exhibited the ribbon pattern that develop along the two major arteries–
Tiwanon and ChaengWatthana. The analysis was divided into two parts: (1)
the analysis of land use changes over 10 years from 1996 – 2006 with 5- year
intervals. The land use change were derived from satellite imageries, acquired
in 1996, 2001 and 2006 then analyzed and interpreted with Geographic
Information Systems.
Urban structure in the municipality follows the theoretical pattern. The
study also showed that commercial centers and the high class residential areas
were near the urban centres. Moreover, the prominent urban structure found in
the Sector Theory was the development of residential areas along major roads.
In this study area, Topographic Maps (1954) and (2010) are used with
a Geographic Information Systems to investigate the expansion of settlement.
This analysis revealed that the same pattern of land use changes in the Maubin
District. Besides, major urban structure discovered in the Multiple Nuclei
Model was the same as the development of residential areas along major roads
and the river.
Estimated origin of villages
In geographical analysis on origin of villages in the study area,
autocorrelations is used. The goal of the autocorrelation is to identify the
factors that contribute significantly at 0.00 levels to the explanation of the
variability in the village settlement initiation. To run the autocorrelations
fitting for all variables which are measured from the village centroids to rivers
355
and streams, water bodies and roads on Topographic Maps of 1954 and 2010
among 1648 villages.
As a result, the following variables are significant. These are Euclidian
Distance from water body to villages in 1954 (with highest positive
correlation between 0.45 and 0.82), Euclidian Distance from water body to
villages in 2010(with second highest positive correlation between 0.46 and
0.78), Euclidian Distance from rivers and streams to villages in 1954 (with
third positive correlation between 0.47 and 0.65) and Euclidian Distance from
rivers and streams to villages in 2010 (with fourth positive correlation
between 0.46 and 0.66).
No autocorrelations are found on Euclidian Distance from road to
villages in 1954 and 2010.Therefore, previous origin of villages are highly
correlated with water bodies and rivers and streams and it is significant at 0.00
levels. From the above results origin of village shows a relationship with
water bodies, rivers and streams. This can be assumed that people tend to
settle closer to rivers and water bodies instead of roads which are further away
from previous existing village centre.
Varnahovida. pet al applied multiple spatial logistic regressions
(Moran’s I and Geary’s C Autocorrelation) using Kernel density, Euclidian
Distance and elevation to investigate and their models could easily be applied
to any rural settings in Thailand and many other locations. This analysis
attempted to identify whether village occurred or not. In this study, Euclidian
Distance with autocorrelation is used and applied to investigate the estimated
village originations. The target of the value at (0.00) level to explain the
variability in the village settlement distribution was applied. In general, null
hypothesis is rejected and alternative hypothesis is accepted.
Spatial and Temporal Changes of Settlement
Town Settlement Pattern
The terms city and town denote nucleated settlements, multifunctional in
character, including an established central business district, and residential
and nonresidential land use. Towns are smaller in size and less in functional
complexity than cities but it still has a nuclear business consideration
(Fellmann, Getis and Getis).
356
In many developing countries, residence of the core city lack
sufficient living space. People can buy more living space in the country side
than in the inner city, since the cost of property is less in these areas.
However, consumption of more living space does not always cause sprawl.
Population density is a major concern in this issue (Bhatta 2010, p 24).
Figure 2 Settlement Patterns during the period (1954 -2010)
Source: Spatial database from Topographic maps, 1:63360 No. 85-O-7, 85-O-8, 85-O-11, 85O-12, 85-O-16and 85-P-5, 85-P-6, 85-P-9, 85-P-10, 85-P-13, 85-P-14) and 1:50000,
No.1695-1, 1695-5, 1695-6, 1695-9, 1695-10, 1695-13, 1695-14, 1795-4, 1795-7,
1795-8, 1795-11, 1795-12, 1795-1
357
The first and foremost reason of urban growth is increase in urban
population. Rapid growth of urban areas is the result of two population growth
factors: (1) natural increase in population, and (2) migration to urban area
(Bhatta 2010, p 18-19).
The Multiple Nuclei Model, described by geographers Harris and
Ullman, suggested that many nuclei, or activity centers, shape land uses in the
city. A Multiple-Nuclei Model which postulate that large cities develop by
peripheral spread from several nodes of growth, not just one. Individual nuclei
of special function-commercial, industrial, port, residential are originally
developed in response to the benefits accruing from spatial association of like
activities in Figure 3.
Figure 3 A Multiple-Nuclei Model
Source: “The nature of cities” by C.D Harris and E.L Ullman in volume no.
Annals of American Academy of Political and Social Science
242 of The
Towns in Maubin District
The Multiple Nuclei Model is applied for analyzing spatial patterns of
urban centres of the study area with some modifications, according to
geographers Harris and Ullman. The multiple nuclei model clearly indicates
an urban area as a collection of individual centres, around which different
people and activities cluster.
Maubin
In 1973, Maubin was the headquarter of Maubin District. There
were588 houses and 1178 people living in 1877. In 1921, there are 1147
houses and 6125 persons in Maubin. It is located on the western bank of
AyeyarwadyRiver and is situated as a narrow linear pattern along the
meandering river bank within the embankment. Two main roads run south to
358
north. Settlement with business areas ware situated along the river bank.
Market, high school, hospital and offices were located there. At that time, the
area of the town was 391.74 hectares (968 acres). Human settlement area was
highest (298.25 hectares) or (736.98 acres) in town land use. Settlement area
was found between Aung Zeya Road and Strand Road. Due to the civil war
the immigrants from villages of Pantanaw and Danubyu were forced to settle
down in Maubin. Therefore, expansion of settlement area was found on north
and western part of the town. The whole of the area is situated on poor
drainage area.
6
Indices
1. Town Center
2. Local Business Area
3. Residential Wards
4. Outlying Business Area
5. New Residential Area
6. Industrial Area
1
2
6
3
Housing Quality
64
3
1
4
4
3
High
Medium
Low
5
Figure 4 Multiple-Nuclei Models of Maubin (1973 and 2010)
Source: Google Images and Land Records Department (Maubin District)
Recently, the town area is 610.27 hectares (1508 acres) and it has
511.93 hectares (1265 acres) of settlement areas in Maubin. Although, New
Residental Areas are sprawl toward northern and southern part of the town,
Town Centre, Business Area and Outlying Business Areas are expanding
along the Toe River in Figure 4.
Pantanaw
Pantanaw is situated near the junction of PantanawRiver and Bawhdi Creek.
In 1887, there was a population of only 5824. It had 989 houses and a
population of 4678 in 1911, but in 1921 there were 1063 houses and 5059
inhabitants. In 1973, there were 1982 houses and 11112 people in
359
PantanawTown. The town has undertaken sedimentation as the
PantanawRiver is becoming shallower. During the dry season, launches can
go up the river only as far as WedaungVillage whiles the rest of the journey to
the town by a sampan or a motor boat. A considerable proportion of the
inhabitants are now engaged in weaving mats (thinbyu). It has a small
hospital, a market and a bungalow. The pattern of the town might be
developed as linear pattern, a big village along the river. At that time, total
area of the town was 206.79 hectares (510.98 acres) and 50 percent of the
town area was agricultural land. Settlement area was only 71.63 hectares or
177 acres (34.64 percent). There were market, office, oil mill and rice mill
along the bank. Settlement areas were found along the river. Therefore, the
function of the town might be semi urban.
After 1988, town area of Pantanaw is 314.44 hectares (776.99 acres)
and the settlement area has 121 hectares (298.99 acres). The town expanded
not only towards the eastern part across the PantanawRiver but also expanded
along the Yangon-Pathein Road. The expanding settlement was useful for
infrastructure developing in the community. Generally, Pantanaw significantly
expanded among the other three towns while, residential New Residential
Areas sprawl toward northeast and eastern part of the Town centre, Local
Business Area and Outlying Business Area are expanding along the YangonPathein Road in Figure 5.
Nyaungdon
Nyaungdon is located at the junction of the PanhlaingRiver and
Ayeyarwady River. The town is square in shaped and do not resemble to that
of other towns in Maubin District. In the period of Myanmar Kings, there
were only 100 houses. In 1973, the area of the town was 267.09 hectares
(659.99 acres) and 20618 people settled. It had two main roads along the river
bank.
360
4
3
2
1
6
6
Indices
1. Town Center
6. Industrial Area
6 4
3
Housing Quality
5
5
3
1
4
4
2
3
4
5 6
High
Medium
Low
6
Figure 5 Multiple-Nuclei Models of Pantanaw (1973 and 2010)
The town dwellers are concentrated within the framework of the embankment
that is fringing the town. During 1970 and 1983 many houses in the western
part of the Ayeyarwady River were washed away due to the collapse of the
river banks through water erosion. To protect from those damage, the
construction of embankment was made. It is located western on the bank of
the town areas expanded southward due to the collapsing of river bank. Now,
the area of the urban land is 339.94 hectares (840 acres) and land use of
residential area is 48.64 hectares (120.19 acres). After collapse of river banks,
four wards of residential areas are expanded and New Residential Areas were
sprawl eastwards in Figure 6.
Danubyu
Danubyu resembles Maubin. It is located on the western bank of
Ayeyarwady River. It is one of the historical towns in Myanmar. The town
dwellers concentrated between east and west of the framework of the
embankment that is fringing the town. The pattern of the town is linear and
situated along the Ayeyarwady River. In 1973, the area of the town is 288.24
hectares and there were 19900 people and 3881 houses.
361
6
6
4
2
1
6 6
6
3
6
Housing Quality
1
2
3
Indices
1. Town Center
6. Industrial Area
4
4
3
5
High
Medium
Low
Figure 6 Multiple-Nuclei Models of Nyaungdon (1973 and 2010)
In recent times, total area of the town is 186.16 hectares (460 acres)
while residential area has 112.50 hectares (277.99 acres). Town Centre, Local
Business Area and Outlying Business Area areas are situated almost along the
Ayeyarwady River.
Generally, with the exception of the Nyaungdon spatial distribution
pattern of urban settlement in the study area is almost similar for the three
towns. In the study area, the models of the towns follow with a MultipleNuclei Model in Figure 7.
362
6
5
6
Indices
1. Town Center
6. Industrial Area
4 21
6
5
3
4
Housing Quality
1
2
3
High
Medium
Low
Figure 7 Multiple-Nuclei Models of Danubyu (1973 and 2010)
Findings and Dicussion
There have been changes of settlement and transportation of Maubin
District during the studies period. The government has also laid down plan for
regional development. But development pattern vary with different part of the
study area.
From the Topographic Maps of (1954) and (2010), it was found that
the expansion took place along the main transportation route within the study
area. The settlement shows a cluster pattern at intersection of roads and began
to expand along the roads and waterways as ribbon development or linear
pattern development. It is noted that, during 1954 -2010 there were changes in
town area as well as village areas. In 1954, towns and villages were covered
157.93 square kilometres and 209.41 square kilometres in 2010. Total
expanded area was 51.48square kilometres. It was mainly due to the
expansion of transportation, both roads and waterway. Therefore, a rapid
change in basic transportation makes a rapid expansion in the enlargement of
linear and compact settlement patterns.
363
From the above result estimated origin of village shows a relationship
with water bodies, rivers and streams. From the result of Autocorrelation
village occurrence shows a relationship with water bodies, rivers and streams.
This can be assumed that people tend to settle closer to rivers and water
bodies instead of roads which are further away from previous existing village
centre.
A Multiple-Nuclei Model is applied to explain the urban pattern of the
study area. The Multiple-Nuclei Model makes clear as an urban as a collection
of individual centre, around with different people and activities cluster. The
model of the towns is followed by a Multiple-Nuclei Model. Although, New
Residential Areas sprawl toward north and southern part of the Maubin,
Town centre area, Local business areas and Outlying business areas are
expanding along the Toe River. Generally, Pantanaw had significantly
expanded among the other three towns due to the improvement of
transportation.Town Centre, Local business areas, and Outlying business areas
are situated almost along the Ayeyarwady River in Danubyu. Generally, with
the exception of the Nyaungdon, spatial distribution pattern of urban
settlement in the study area is almost similar for the three towns in the study
area. The model of the towns is followed with a Multiple-Nuclei Model.
Besides, major town structure discovered in the Multiple Nuclei Model was
the development of residential areas along major roads and along the river.
Conclusion
This study is necessary to analyze the past and present conditions on
distribution of settlement pattern and infrastructures of the inhabitants. Present
settlement patterns may be the response of various controlling factors.In the
early period, Maubin District appeared to have been little known before the
Alaung Paya Dynasty and the population was scanty.Settlement forms and
patterns of the study area shows generally cluster and random. The
combination of nearby villages along the bank of Ayeyarwady River, Toe
river, Pantanaw River, Shwelaung River and Panhlaing River and creeks, at
the places of road junctions and at the places where major transportation route
parallel to the river which cause to have linear settlement pattern and a group
of villages clustered.Finally, in this study found out less accessible villages in
the study area has isolated, low clustered and random pattern.
364
References
Bhatta, B. (2010): Analysis of Urban Growth and Sprawl from Remote Sensing Data,
Springer Heidelberg Dordrecht London New York,P-2.
Chou,Y.H. (1997): Spatial Pattern and Spatial Autocorrelation, Department ofEarth
Sciences, University of California.
Fellmann J, Getis A, Getis J (1990): Human Geography, Landscapes of Human Activities,
University of Illinois, Urbana Champaign, U.S.A. PP 364-3
Harris, C. D, and Ullman, E. L. (1945): The nature of city. Annals of the American
Academy of Political Science, 242.
Sukawattanavijit, C. (2006): Study of Urban Evolution and Settlement Patterns of Pak
Kret Municipality, Changwat Nonthaburi by Using Satellite Data, GeoInformatics and Space Technology Development Agency, Thailand.
Varnakovida, P. Mohamed, A. Witchakool (2000): Spatial Pattern Analysis of Settlement
Locations Using Logistic Regression. Department of Geography,
Department of Statistics,Michigan State University.

Journal of the Myanmar Academy of Arts and Science Vol. XI, No. 6

Transcription

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