Understanding Montney reservoir heterogeneity: A geo

Understanding Montney reservoir heterogeneity: A geo

Understanding Montney
reservoir heterogeneity: A
geo-engineering approach
Genga Nadaraju and Dan Elliott
Encana Corporation
Calgary | June 21st | 2010
Montney Resource Play
Tight Gas Fairway
on
M
tn
ey
Montney
Alberta
2 00
Su
bc
ro
p
ge
Ed
200
10 0
50
Fr
on
t
150
n
2 00
or
m
at
io
200
150
BC
10 0
D
ef
Montney Tight Gas
Fairway ~ 520 Twp.*
*1 Twp ~ 23,040 acres
Paleogeography – Lower Triassic
Modern Analog – West Africa
• 251 MYA -245 MYA
• 30 degrees N paleolatitude
Europe
• Hot, seasonally arid, seasonal rain
• BC and west AB covered by water
Modern Analogy – West Africa
Modern Alberta
• 30 degrees N latitude
• Hot, seasonally arid
• Aeolian component
N.America
West Africa
PANGEA
Dust Storm
Montney Resource Play
Tight Gas Fairway
on
M
conventional
tn
ey
2 00
Su
bc
ro
p
ge
Ed
10 0
200
150
10 0
50
Fr
on
t
200
n
2 00
or
m
at
io
150
D
ef
Unconventional
BC
Alberta
Montney Resource Play
Tight Gas Fairway
Conventional
Unconventional
Montney Tight Gas
Fairway
FARRELL
GROUNDBIRCH
BASIN – CENTERED SYSTEM
HLFY: BASIN
CENTERED GA
S
SYSTEM ?
MONIAS
SUNSET
SUNRISE
SWAN
DAWSON,
PARKLAND
DOIG
GORDONDALE
High Pe
rm
ATSB
ATSB
SILT
CONVENTIONAL
SYSTEM
DOIG PHOSPHATES
(8-15%TOC)
Low Perm
LOWER MONTNEY
UPPER MONTNEY
SOURCE/RESERVOIR
(1-2% TOC)
Type 2 oil prone
TURBIDIT
ES
BELLOY
BC
ALTA
Montney Tight Gas
Development area
BC Alberta
Montney Tight Sand Gas
 High OGIP area
 Full development since 2006
Fort St John
BC
Alberta
Dawson Creek
Grande Prairie
OGIP Map
High
Medium
Low
20mi
32km
BC
Alberta
Montney Tight Gas
Stratigraphy
BC ALTA
Doig Phosphate
Transgressive
Surface
Mid Montney
Marker
Sexsmith
BELLOY
Lower Montney
Upper Montney
Lower
Doig
Montney Tight Gas
Established development areas
BC
Alberta
• Do we see heterogeneity
distribution of Montney
facies across the area?
Septimus
Parkland
Dawson
Doe
Groundbirch
Gordondale
BC
Sunrise
Glacier
Sundown
Upper Montney
Lower Montney
Swan
Tupper
Alberta
Understanding Montney reservoir heterogeneity
Talk Outline
Geological approach
• Montney Resource play technical driver
•
•
•
•
•
Maturity
Pressure
Rock properties,
Permeability
Thickness, porosity & OGIP
• Montney Depositional Models
•
Upper vs. Lower Montney
Engineering approach
• kh not always correlated to h
• Statistics is the tool which quantifies variability
•
Regionally, inter-well, inter-frac
• Different Montney completion techniques
• IP plots
Montney Resource Play
Technical Drivers
Spider Diagram
OGIP (Bcf/sect.)
THICKNESS (ft.)
140
35 0
100
POROSITY (%)
10
0
MINERALOGY
(% Non-Clay)
25 0
14
15 0
60
10
80
60
6
ADSORBED
GAS (scf/t)
105
75
45
1.4
1.8
2.2
MATURATION
(Ro%)
3
.55
.65
5
5
.75
.20
7
PRESSURE GR.
(psi/ft)
7
.10
YOUNG’S MODULUS
(mmpsia)
9
0
POISSON’S RATIO
TOC (%)
Montney Tight Gas
Maturity and Pressure Elevation plots
Normal Pressure Gradient
GORDONDALE
E
R
TU
A
M
H
F a ay
ul Ri
t Z ve
on r
e
Alberta
DAWSON
GROUNDBIRCH
E
UR
AT
RM
VE
O
Contour Interval = 10oC
60 points
SWAN
CUTBANK
BC
Montney Maturity Map
Regional Over
Pressured
system
Tm
ax
=
45
5
32 km
20 mi
Montney Tight Gas
Rock properties
• Brittle and Stiff
• Fractures easily
• Silica and dolomite
9
Montney
Mean data
L
U
8
content
• Variability
Montney
scatter
•
5
•
4
Absence or presence of
natural fracture
Scatter in the Poisson’s
ratio and Young’s
modulus
3
2
1
COMPLIANT
Young's mod mmpsi
6
STIFF
7
DUCTILE
BRITTLE
0
0.0
0.1
0.2
0.3
Poissons Ratio
0.4
0.5
ECA Shale plays
Modified from D. Potocki
Backscatter SEM
Effect on grain size on effective porosity
Total Porosity
Effective Porosity
6.2%
1.0%
6.2%
0.9%
Medium Silt
Medium Silt
6.3%
2.6%
6.2%
2.7%
Coarse Silt
Coarse Silt
 Decreasing grain size & permeability
Basinward
Black = pore space
Light Grey = dolomite
 Variability in sorting & pore throat size
Matrix perm play
Dark Grey = quartz
White = pyrite
Modified from J. Wood
Montney Tight Gas
Resource Pyramid
Upper Montney
3% 0%
A
Lower Montney
3% 0%
Mid Mont.
Prod
RGIP
B1
~100m developed
~135m pay High-graded
zones
B2
~165m pay at 3% porosity
Water production
~250m pay at 0% porosity
C
Sexsmith
D
Lower perm
Upper Montney Geology
Basinward Clinoform Depositional Model
BC Alberta
Basin-ward
Prograding
Slope Edge
Groundbirch
Sunrise
Parkland
Dawson
Glacier/Doe
Decreasing grain size and permeability (Per clinoform)
EAST
WEST
Groundbirch
Graben
Structural
Flexure
Upper Montney Depositional Environment
Facies (Outer Shoreface, Transition, Offshore)
Facies 1
Airborne sand transport
Density Flow
Density
Flows
Facies 2
Facies 3
Upper Montney Depositional Environment
Comparison of Facies in Core
Basin Ward
Shore Ward
Outer Shoreface - Transition
Bioturbated light grey siltstone deposited
in a well oxygenated setting between
storm and fair weather wave base.
Facies 1
Offshore - Transition
Interbedded light and dark siltstone deposited
above storm wave base in a generally quiet
setting with episodic rapid deposition.
Facies 2 proximal
3 - 4 inches
Facies 2 distal
Offshore
Relatively organic rich pinstripe
lamina of dark grey siltstone
deposited below storm wave base.
Facies 3
Upper Montney Geology
Offshore-transition Depositional Environment
Lenticular Bedding
Mud drape
Ripple & cross laminated
Tempestite : storm dominated
Parallel laminated
Sharp base with scours
Density Flow
Upper Montney
Established development areas
BC
Alberta
Groundbirch
Septimus
Parkland
Dawson
Parkland
Dawson
Groundbirch
Sunrise
Swan
La
te
•
Development areas in
different section of the
clinoform
•
Thicker section to the
west
•
•
Structural control
Fluid issues :
condensate, oil and
water
ra l
va
ri
ati
on
Swan
in
r es
er v
oi r
qu
a li
ty
wet
Different type curve areas
Inter-well
Int
erfra
c
Local variation
Lower Montney Geology
Proximal to Distal Ramp Turbidite Depositional Model
BC
Alberta
se
crea
d de e
r
a
in w ain siz
Bas
gr
in
Ma
ss W
Slo asting
pe
Bre along
ak
ce
refa
Sho
Off
s
Sto hore
T
rm
Dep ransi
osi tion
ts
–
xim
Pro p
m
Ra
al
Dist
p
m
Ra
al
Fault
Reactivated
Zone
Lower Montney Core
Sexsmith
• Massive and homogeneous
• parallel laminated
Lower Montney
Sexsmith established development areas
BC
se
crea
d de
r
a
in w
Bas in size
ra
in g
Alberta
Ma
ss W
Slo asting
pe
Bre along
ak
ce
refa
Sho
Gordondale
Off
s
Sto hore
T
rm
Dep ransi
osi tion
ts
–
Swan
Glacier
Tupper
•
•
•
•
Smaller areal extent (so far)
Proximal to Distal facies
Structural influences.
Less fluid risk
Different type curve areas
xim
Pro p
m
Ra
al
Dist
p
m
Ra
al
Fault
Reactivated
Zone
Montney reservoir heterogeneity
Geo-engineering approach
Por. &
Neutron/
G Porosity Porosity BVW
R
1950
RHOB_2
K/M3
2950
0.45
NPSS_1
V/V
-0.15
MD
BC
Alberta
0
GR_1
GAPI
200
EVAL_MONTNEY.VOL_UWAT_N
0.15
V/V
0
EVAL_MONTNEY.PHIT_1 EVAL_MONTNEY.PHIT_1
0.15
V/V
0 0.15
V/V
0
2451.5
2451.5
Septimus
Parkland
2500
Dawson
Groundbirch
Gordondale
2550
2600
Sunrise
Swan
2650
2700
Upper Montney
Lower Montney
2750
2754.0
2754.0
• Development areas
• Heterogeneous reservoir
• Drill the wells
• IP rates are indicative
of permeability
• Range points to the
reservoir heterogeneity
Understanding Montney reservoir heterogeneity
Talk Outline
Geological approach
• Montney Resource play technical driver
•
•
•
•
•
Maturity
Pressure
Rock properties,
Permeability
Thickness, porosity & OGIP
• Montney Depositional Models
•
Upper vs. Lower Montney
Engineering approach
• kh not always correlated to h
• Statistics is the tool which quantifies variability
•
Regionally, inter-well, inter-frac
• Different Montney completion techniques
• IP plots
kh not always correlated to h
• Relative permeability one key
• Water and Condensate
• Fluid can drastically reduce small pore throats
Inter-well Variability
La
te
ra l
va
ri
ati
on
in
r es
er v
oi r
wet
A-D22-H
1.3
42
0m
A-C22-H
1.0
D-B25-H
2.2
D-A25-H
2.0
Initial Production Rates (mmcf/d/frac)
qu
a li
ty
Inter-well Variability
Inter-well
kH
Local variation
Initial 48 hour IP (Mmcf/d/Frac)
Inter-Frac Variability
Initial Rates (E3m3/d)
Frac 6,
8.0
Frac 5,
26.8
Frac 4,
16.9
Frac 7,
102.4
Frac 5,
42
Heel
Heel
Frac 6,
26.9
Frac 3,
20.5
Frac 1*,
3.3
Frac 2*,
3.3
D-C9-H Horizontal well
Frac 1,
13.7
Frac 4,
17
Frac 3,
0
Frac 2,
15.7
D-B5-H Horizontal well
~1600m HZ length 150 – 200m frac spacing
Heel
#8
Toe
Variability between fracs
#1
ECA Swan Upper Montney IPs
La
te
wet
Cum. Probability
Swan Upper Montney HZ
Mean/Average = 1.3
P90/P10
= 0.4/2.6
2/3 data below mean
Mean/Average
Initial Production/Frac (mmcf/d) – pressure normalized
ra l
va
ri
ati
on
in
r es
er v
oi r
qu
a li
ty
Various Montney Completion Techniques
• Reservoir Access
• Perforations, Jetted Slots/Holes, Frac Sleeves
• Local perforation points, cluster perforations (limited entry),
open hole packer systems
• Isolation/Diversion
• Bridge Plugs (BPs), Sand Plugs, Frac Balls
Frac Sleeves & Open Hole Packers
Perforations and Bridge Plugs
Jetted Holes and Sand Plugs
Various Montney Completion Techniques
• Fracture Stimulation Techniques
• Slickwater, CO2/N2 energized systems
• Proppant Type and Tonnage
• 40/70 to 20/40 Sand
• Ranging from 50 to 200 tonnes
• Resin coated tail-ins
Frac Sleeves & Open Hole Packers
Perforations and Bridge Plugs
Jetted Holes and Sand Plugs
Various Montney Completion Techniques
BC
Alberta
•
Advantage
•
Storm
•
ARC
•
•
ARC
Shell
•
ADV
Murphy
•
Open hole packers & CO2
fracs
Cluster perfs and CO2 fracs
Low volume slickwater & Open
hole packers
Shell
•
•
Sand Plugs and N2 fracs
Murphy
•
•
ECA
Sand Plugs/BP and CO2 fracs
EnCana
•
•
ECA
Perfs & BPs & CO2 fracs
Cluster perfs and low volume
slickwater
Storm
•
Perfs & BPs & CO2/N2 fracs
Advantage, Murphy, ECA
Upper Montney IPs
BC
ECA
AB
Advantage
Cum. Probability
Murphy
Initial Production/Frac (mmcf/d) – pressure normalized
BC
Murphy and ECA
AB
ECA
Lower Montney IPs
Cum. Probability
Murphy
Initial Production/Frac (mmcf/d – pressure normalized)
ARC, Storm, ECA
ECA
Cum. Probability
Upper Montney IPs
Storm
Initial Production/Frac (mmcf/d – pressure normalized)
BC
ARC
Shell, Storm and Various Competitors
Initial Total Well Rate
Shell/Shell
Storm
Cum. Probability
ECA et. al.
1.0
10.0
48 Hour Total Well rate (mmcf/d – pressure normalized)
100.0
Shell, Storm and Various Competitors
Shell/Shell
ECA et. al.
Storm
Cum. Probability
Initial Total Well Rate – Length Normalized
1.0
10.0
48 Hour Rate (mmcf/d – normalized to 1600m)
100.0
Shell Slickwater/Cluster Perf vs. CO2 fracs
Initial Total Well Rate – Length Normalized
Conclusions
•
•
Reservoir quality (effective kh) will drive results
Reservoir access/design most important variables to manage
• Well Length/Interfrac spacing strongly tie to well initial production
rates
•
Fracture Stimulation design to date can provide some initial rate
improvements (10-20%):
• Needs to be properly quantified against reservoir variability