the geology and discovery of the garden well gold deposit, western

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the geology and discovery of the garden well gold deposit, western
THE GEOLOGY AND DISCOVERY OF THE GARDEN WELL
GOLD DEPOSIT, WESTERN AUSTRALIA
Jens Balkau
Australian Institute of Geoscientists 15 May 2013
Forward-Looking Statements
This presentation contains “forward-looking statements”.
without limitation:
Such forward-looking statements may include,
 Estimates of future results of exploration activities;
 Estimates of future cash flow;
 Estimates of future capital expenditure and resources;
 Estimates of mineral reserves, resources and statements regarding future exploration results.
Where the Company expresses or implies an expectation or belief as to future events or results, such
expectation or belief is expressed in good faith and believed to have a reasonable basis. However, forward
looking statements are subject to risks, uncertainties and other factors, which could cause actual results to
differ materially from future results expressed, projected or implied by such forward-looking statements. Such
risks include, but are not limited to metals price volatility, currency fluctuations, increased production costs and
variances in ore grade or recovery rates from those assumed in mining plans, as well as political and
operational risks in the countries and states in which we operate or sell product to, and governmental
regulation and judicial outcomes.
The Company does not undertake any obligation to release publicly any revisions to any “forward-looking
statement” to reflect events or circumstances after the date of this presentation, or to reflect the occurrence of
unanticipated events, except as may be required under applicable securities laws.
The Geology and Discovery of
the Garden Well Gold Deposit
•
•
•
•
•
•
•
Location & Tenements
Historical Production
Discovery History
Geology & Geochemistry
Resources & Development
Production
Conclusions
Western
Australia
Location and
Tenements Duketon
Gold Project
 Located 350km NNE of
Kalgoorlie
 100% Regis owned
Moolart Well
Garden Well
50 km
Duketon Gold Project
Location Garden Well
 Garden Well 100km N of
Laverton
 35km S of Moolart Well
 387 granted leases
GRANNY SMITH
 1,220 km² of ground
Tenements
Duketon Gold Project
 Moolart Well 2001
10 km
 Garden Well 2009
 Duketon Gold Project:
10 deposits granted ML’s
 7.6 Moz Au Resources
 3.0 Moz Au Reserves
Cox’s Find
Duketon Historical Production
Duketon Greenstone Belt,
Mt Margaret Goldfield in
1906
Duketon
Greenstone Belt
Moolart Well
 Duketon, Erlistoun and Mulga
Queen mining centres in
1890’s
Garden Well
 Production short lived
 Moolart Well never
prospected or drilled till 2001
Laverton
 Garden Well never
prospected or drilled till 2008
Historical Production to 1905
Mistake Gold Mine Erlistoun
Mining
Centre
Tons of
Ore
Fine ozs
Gold
Golden Spinifex Battery Duketon
Grade oz
Duketon
4,850
4,125
0.85
Erlistoun
4,927
5,357
1.09
Mulga
Queen
8,020
6,379
0.80
Other
5,873
6,624
1.13
Total
23,670
22,485
0.95
Famous Blue Gold Mine Mulga
Queen
Production figures to 1905
Historical Production in 1990’s
Operation
Production
Tonnes
Grade
g/t Au
ozs
Au
Year
Christmas
well
222,000
2.65
16,600
1991-93
Russells
Find
115,800
3.28
12,250
1992-93
Reichelts
Find
300,000
4.44
43,000
1990-93
Total
637,800
3.55
71,850
1990-93
Russells Find
Reichelts Find
Christmas Well (Rosemont)
Total Historical Production
Duketon Greenstone Belt
 Total historical gold production from 1896 till July
2010 (114 years) approx 120,000oz
 Moolart Well gold production August 2010 to March
2013 (32 months) 266,053oz
 Garden Well gold production September 2012 to
March 2013 (7 months) 117,157oz
 Total Regis production since August 2010, 383,210oz
 Rejuvenated DGB in 2.5 years
DGB Gold Endowment:
Pre 2001
Deposit
900
800
700
600
500
400
Resource (koz)
300
200
100
0
DGB Gold Endowment:
Post 2001
2500
2000
Deposit
Potential for a 5-10Moz deposit?
1500
1000
500
0
Resource (koz)
Erlistoun
syncline
Lulu
Fault
Duketon Greenstone Belt
Geology and Structure
Moolart
Well
Garden
Well
 Garden Well on eastern limb of
Erlistoun Syncline
 Confluence of N-S and NNWSSE faults
 Ultramafic and sediment host
rocks
Mulga
Queen Duketon
Moolart
Well
Duketon Greenstone Belt
Aeromagnetics
First derivative Aeromagnetics
 Multiple controlling structures
Rosemont
Detail study area
Garden
Well
 Regional N-S trending sinistral
strike slip fault
Erlistoun
25 km
Gold Occurrences
Gold Resources
 NNW-SSE trending cross faults
 Located 35km S of Moolart Well
Garden Well Discovery History
 No historical gold 1890’s workings
 No drilling in 1990’s gold rush but close!
 Sep 2001 Moolart Well discovery
 2006 start exploration for Moolart type undercover deposits
 November 2008: Ten Aircore holes drilled over Garden Well
Test 8 to 75ppb gold lag soil anomaly
 Discovery November 2009: 18 further Aircore holes.
GDAC002, 47m @ 2.58g/t Au from 77m to 124m EOH
Garden Well Discovery
Moolart, Garden Well Geochemistry
σ'
Moolart
Well
603koz Au
Pleco
Moolart
Well
σ'
Garden Well
1,660koz Au
σ'
Garden
Well
2km
σ'
2km
438000 mE
437000 mE
436000 mE
6914000 mN
Ultramafic
Sediments
Diorite
Garden Well
Discovery First
Drilling Nov 2008
 8 - 75ppb Au soil anomaly on
edge of palaeochannel
 10 Aircore drill holes on
6913000mN Nov 2008
6913000mN
6913000 mN
6912000 mN
Tertiary Palaeochannel
3 to 7ppb Au Lag Soil
6911000 mN
O
1km
8 to 24ppb Au
>25 ppb Au
Garden Well Discovery
Nov 2009 Aircore Drilling
1km
Discovery Aircore drill line
Tertiary Palaeochannel
Pre 2008 Historical Drilling
Garden Well 1gm Au outline
3 to 7ppb Au Lag Soils
8 to 24ppb Au
25 to 74 ppb Au
>74 ppb Au
0
1km
2km
Garden Well Discovery Nov 2009
Aircore Drilling
Shear Zone Mixed
Ultramafic/Sediment
Package
1km
Discovery Aircore drill line
Garden Well Discovery
First Aircore Drilling
500 m RL
Saprolite clays
3-8ppb
Au lag
160 metres
Alluvial clays and sands
450 m RL
436900 mE
436700 mE
436500 mE
 Aircore holes 160m apart across 8 to 75ppb gold lag soil anomaly
 Narrow zones in weathered ultramafic under palaeochannel clay
Untested
Untested
450 m RL
Saprock
Diorite
Sediment
Garden Well 691300mN
1.88 6 Gold g/t Metres
Gold Mineralised zone
400 m RL
Ultramafic
Garden Well Discovery
Nov 2009 Aircore Discovery Drilling
500mRL
First holes 160m apart
Saprolite
and
Saprock
450mRL
400mRL
50 metres
Open
436750mE
Garden Well 6913000mN
1.88 6 Gold g/t Metres
Gold Mineralised zone
436650mE
Ultramafic
Sediment
Sheared Ultramafic & Sediment
350mRL
Garden Well Discovery Drilling
GDAC084
GDAC085
First Aircore holes on Discovery Traverse 6913000mN
View West from GDAC086 across Palaeochannel
Garden Well Discovery
Post Discovery Drilling
 Nov 2009 to Mar 2013 drilling
 240 Aircore holes for 21,656m
 387 RC holes for 76,726m
 108 diamond holes for 40,919m
 Total 139,300m in 28 months
 Resource 2.14 Moz Au and Reserve 1.66 Moz Au
March 2011
 Discovery Cost <$5 per resource ounce
 Deposit is open to the south. Drilling in progress
Garden Well Geology and
Geochemistry
Sediment
6914000mN
6914000mN
Garden Well
1gm Au outline
NonBIF
Magnetic
Ultramafic
Discovery drill line
Magnetic
Ultramafic
6912000mN
Pre 2008 Historical Drilling
3 to 7ppb Au Lag Soils
8 to 24ppb Au
25 to 74 ppb Au
>74 ppb Au
Diorite
6912000mN
>1 g/t Gold All Drilling
0.5 to 1.0 g/t Au
0.25 to 0.5 g/t Au
0.01 to 0.25 g/t Au
<0.01 g/t Au
Garden Well Gold gram-metre drill
intercepts: December 2011
Gram Metre Au
Plan Projection
BIF
Higher Grade
Shoots Open
at Depth
Ultramafic
Shale
Open
to
South
 Three high grade
shoots >80gm
 High grade shoots
plunge SE
 Deposit open at
south end
Shear Zone Mixed
ultramafic/Sediment
under Palaeochannel
Garden Well Gold gram-metre drill
intercepts: December 2011
Discovery Line
Section 6912680mN
Garden Well Geology; Cross section
6912680mN
Calcrete
Lacustrine clays and gravel base
100m
Oxidised Zone
Kaolinite clays
Shear zone 1 to 2%
disseminated sulphides
Carbonaceous black shale
Minor 1-2% sulphides
Talc-dolomite-chlorite
No sulphides
Garden Well GDAC001 Oxide,
Transition and Fresh Rock Zones
Authigenic
130m Pisoliths
Fresh rock 130 to 133m
Fresh Rock Zone
Transition
Zone
Saprock 80 to 130m
80m
Saprolite Clays 35 to 80m
Oxide Zone
35m
Lacustrine Clays 7 to 35m
7m
Calcrete 0 to 7m
Tertiary
Palaeochannel
Cover
Garden Well Geology; First Aircore
holes in 2008
Sheared altered ultramafic
Quartz-dolomite fuchsitechlorite-pyrite alteration
Black Carbonaceous shale
LKAC085: 8m @ 1.61 g/t Au from 72 to 80m and
10m @ 2.22 g/t Au 96 to 106m EOH
Garden Well Geology
Gold Grades GDAC005
GDAC005: 69m @ 4.26g/t Au from 42 to 111m EOH including;
•18m @ 11.32g/t from 42m
• 5m @ 3.85g/t from 63m
• 10m @ 1.65g/t from 79m
• 17m @ 2.95g/t from 94m
79m
Oxide Zone
Transition Zone
17m @ 2.95g/t from 94m 94m
10m @ 1.65g/t from 79m
EOH 111m
5m @ 3.85g/t from 63m
18m @ 11.32g/t from 42m
63m
Transition
Zone
Oxide
Zone
42m
36m
10 to 36m Lacustrine
clays
0 to 10m Calcrete
Tertiary
Palaeochannel
Cover
Down Hole
Garden Well Geology
Transition Zone: GDAC018 74 to 80m
Black carbonaceous shale
74 to 75m
0.002g/t Au
75 to 76m
0.001g/t Au
76 to 77m
0.003g/t Au
Sheared peridotite cb-si-fu-py
77 to 78m
36.2g/t Au
78 to 79m
4.03g/t Au
79 to 80m
5.04g/t Au
Garden Well Geology
Visible Gold from RC Drilling
 Gold is coarse and easily panned from all zones
 Metallurgical recovery in all zones >92%
Oxide Panned Gold
Upper Saprolite
Transition Panned
Gold Lower Saprolite
500 microns
500 microns
Hypogene Panned
Gold Fresh Rock
500 microns
Garden Well Geology
Visible Gold from RC Drilling
 Most gold associated with late stage quartz-carbonate veining
500 microns
500 microns
Quartz
Gold
Gold
Quartz
Pyrite
Garden Well Geology
Visible Gold from Diamond Core
Gold
Dolomite-chlorite-fuchsite-pyrite
500 microns
Quartz-dolomite vein
Garden Well Geology
Visible Gold from Diamond Core
2mm
Quartz-dolomite vein
Chlorite-fuchsitedolomite-pyrite
Garden Well Geology
Oriented Core GDDD027 288.8m
Diamond Hole DD027
Dip 50° West. View
North
50°
500 microns
Gold
60° to 075°
Shear
Fabric
Gold
Chlorite-fuchsitedolomite-pyrite
Visible
Gold
Quartz-Dolomite
Pyrite
Garden Well Geology
Oriented Core Ultramafic Ore Zone
Hanging Wall Black Shale
Mixed Shale
Ultramafic Ore Zone
Quartz dolomite
clinochlore
fuchsite pyrite
alteration
West
East
Ultramafic Ore
Zone
View North
Shear Fabric 60° to 075°
Foot Wall talccarbonate Ultramafic
Garden Well Geology
GDDD001 at 148m Alteration
 Strongly sheared ultramafic with Quartz-dolomite-chloritefuchsite-pyrite alteration (1.5 – 2.0g/t Au)
GW Gold gram-metre drill intercepts:
Results of Recent Drilling
Nov 2011
Nov 2012
BIF
6913280mN
1.84 km
1.16km
6913280mN
Ultramafic
Southern Limit
of Current
Reserves
Southern Limit
of Current
Reserves
Shale
6912120mN
Chert/shale host
Section 6911680mN
Southern Limit of
Drilling 6911440mN
Open
680m
6912120mN
Garden Well Cross Section
6911680mN October 2012
GW Long Section Nov 2012
Test
South
End
Test High Grade
Shoots U/G
Potential?
Garden Well Geology
Chert Shale BIF Ore Zone
Hanging Wall BIF/Chert/Shale
BIF/Chert pyrite
altered Ore Zone
Quartz carbonate
pyrite alteration
Si-cb-py
West
East
Chert/BIF/Shale
si-cb-py Ore Zone
Foot Wall talc-carbonate
Peridotite Ultramafic
Garden Well Geology
Chert Shale BIF Ore Zone
 Strongly brecciated chert/shale with Quartz-carbonate-pyrite
alteration
South of line 6911900mN gold mineralisation hosted
by chert BIF and shale
Garden Well Palaeochannel
Geochemistry (Richard Carver)
3-8ppb
Au lag
100m
Au Ore
Garden Well Palaeochannel
Geochemistry
Cover
Cover Gold ppb
Zone
6913080mN
Au Ore
 No anomalous Au in surface
soil and lag sampling
 8 – 75ppb Au on eastern
palaeochannel margin
 Remobilised Au or truncated
regional Au anomaly?
 Remobilised Au in Eocene
palaeochannel clays up to
1g/t Au (Authigenic pisoliths)
500m
Zone
6912520mN
Garden Well Palaeochannel
Geochemistry
Cover
Cover Gold ppb
6912360mN
Au Ore
6912040mN
8ppb
Au lag
500m
6912040mN
13 to 24ppb Au
Up to 120ppb in
Acacia Aneura
leaves
Water Table
8 to 75 ppb Au anomaly
Lateral remobilisation of Au
in cover sequence over 100’s
metres. Far greater than
vertical remobilisation
Top of Fresh Rock
Garden Well Gold Reserves
Proposed 1.66 Moz Au
Reserve Open Pit
Leapfrog
0.3g/t Au
shell
Garden Well 3D
View to NW
Garden Well Gold Reserves
Production




Discovery hole November 2009
Construction commenced June 2011
Production commenced late August 2012
Total production to end March 2013 - 117,157 oz Au
Garden Well Gold Production
August 2012 to March 2013
Garden Well Camp
August 2011
Garden Well Gold Mill
September 2012
Garden Well Gold Mill
September 2012
Garden Well Open Pit
October 2012: View South
Palaeochannel
First Gold Pour
4 September
2012
Conclusions
What do we Know about
Moolart Well and Garden Well?
 Both under palaeochannels
 Both on regional N-S shear zones
 Both on regional deflection in shear zone
 Both proximal to an ultramafic contact
 Neither deposit directly responds to soil or lag
soil geochemistry
 Both have weak Au soil anomalies on margins of
palaeochannels
 Model for Au in palaeochannel
– Truncated anomalies or leakage anomalies?
Is the Duketon Belt Mature?
DGB has a history of 110+ years of gold
exploration starting in 1896
All gold deposits that crop out have been
found. Belt is mature for exposed deposits
Most past exploration focused on exposed
deposits
Two largest deposits in the DGB found in the
last 10 years under cover
GW discovery to production < 3 years
Is the Duketon Belt Mature?
Both deposits are Blind Virgin discoveries
Resources both Deposits 4.36Moz Au
Reserves both Deposits 2.26Moz Au+
Each Deposit basis of a New Gold Mill
Significant potential for new under cover
gold discoveries in DGB and other belts
Application of geochemistry in
exploration?
Thank You: Questions

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