Uranium Exploration in North West Manitoba

CanAlaska Uranium Ltd.
Uranium Exploration in
North West Manitoba
Ross Polutnik
K. Schimann, R. Duff, S. Napier
Manitoba Mining and Minerals Convention:
Nov 15-17, 2012
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NW Manitoba Project: Outline
• Project Location
• Regional Geology
• Exploration History
• Target Areas
• Geophysical Exploration Model
• Gravity & DC Resistivity Survey
• Comparison with the Andrew
Lake Deposit, Nunavut
• Conclusion
2
Location
Points North
Lac Brochet
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Regional Geology
Eagle Point
Cigar Lake
McArthur River
Key Lake
• Primarily within the Wollaston Domain
immediately East of the Saskatchewan /
Manitoba border.
• Composed predominantly of ca. 2.1-1.9
Ga Paleoproterozoic metasedimentary
rocks of the Wollaston Supergroup.
• Dominated by a strong northeast
trending fabric related to the ca. 1.84 to
1.77 Ga Trans-Hudson Orogen.
• Region underwent extensive glaciation,
and the modern day landscape is
dominated by glacial features.
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NW Manitoba Project
Regional Magnetic Field Map
Manitoba uranium belt
ƒThe extension of the
Saskatchewan uranium
belt
ƒUranium is found in all
rock types
ƒMOU in place with Lac
Brochet First Nations
ƒMaguire Trend targets
drill ready
ƒManitoba drilling
moratorium lifted 2012
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Exploration History
A systematic exploration program across the entire property:
2005
2006
2007
2008
2009
2010
2011
2012
yr.
•
•
•
•
•
Acquired
Ground
Lake Sediment Sampling
Prospecting
Geological Mapping
Boulder and Soil Sampling
Airborne MAG-VLF-RAD
Survey & VTEM Survey
Memorandum of Understanding
(MOU) with the community of
Lac Brochet signed
Exploration put on hold while the
Manitoba Government and First
Nations communities held
consultations
Winter ground geophysics
program
• DC Resistivity
• Gravity
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Lake Sediment Geochemistry
U ppm
# of Lake Sediment Samples = 1831
Maximum Value = 532 ppm U
20 km
U ppm
3 9 16
28
41
53
66
78
91
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Prospecting Samples
Total
Samples
Assayed:
1509
Samples > 1.0 %
U3O8 are clustered
in prospective
target areas
(Background is Lake
Sediment U ppm)
U3O8 > 0.1 %
(1068 Samples - 71%)
20 km
U3O8 > 1.0 %
(86 Samples – 5.7%)
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NW Manitoba Project
Lake Sediment Geochemistry
1831 Lake Sediment Samples
collected from helicopter (see map
dots)
Maximum Value = 532 ppm U
Extensive sampling
lead to Uranium
outcrop and
dispersion trails.
Sample on left is
pitchblende with clay
coating. (>60% U3O8)
U ppm
3 9 16
28
41
53
66
78
91
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Major Target Areas
30 km
Compilation of all exploration data resulted in
the identification of 7 major target areas
requiring follow up work.
Uranium mineralization has been found in many
rock types:
• Calc-silicates
• Pegmatitic tonalites
• Arkosic gneisses
• Amphibolite / pelite / leucocratic granites
Geological mapping and prospecting indicates
that mineralization is frequently associated with
major structural features.
20 km
Property Area: 143,603 ha
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Geophysical Exploration Model
Key Geophysical Exploration Criteria for
Basement-hosted Uranium Deposits:
• Located along a major structure or at the
intersection of crosscutting structures
• Directly associated with a distinct high amplitude
gravity low
• Gravity low is associated with a resistivity low
In Nunavut, the combination of gravity and DC
resistivity surveys has proved to be an effective
exploration strategy in the search for basement hosted
unconformity style deposits.
In 2012 we continued our strategy of defining drill
targets using methodologies employed in Nunavut to
explore for basement-hosted uranium deposits.
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Geophysical Exploration Model
Why are Gravity and DC Resistivity surveys
effective?
DC Resistivity Low Contour
Hydrothermal alteration potentially related to
uranium mineralization generally produces clay
alteration halos that have a lower density and
lower resistivity than fresh host rock.
Andrew Lake / Kiggavik Deposit
Basement hosted unconformity style
Uranium in a clay alteration halo
Coincident DC resistivity low and gravity low
59 million lbs U3O8 at 0.38 %
200 m
Project Area: Andrew Lake + Kiggavik + End Grid Deposits
134 million lbs U3O8 at 0.23 %
Gravity
(Geological Resources from Areva Resources Canada Inc, Report ‘The Kiggavik
Project: Project Proposal’, Nov 2008)
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Priority Targets
Grid 2c
Two Priority Target Areas were identified
Grid 2b
• Grid 1 (Snyder 4)
• Grid 2 (Maguire Trend)
Grid 2a
Grid 1 is located on a broad Archean
antiformal structure.
Grid 2 lies within the Maguire structural trend.
Grid 1
Detailed 2006
Airborne
Magnetic Survey
10 km
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Grid 2: Magnetic Data
Maguire Trend
(Major Structural Trend)
Maguire Graphitic
Conductor
Grid 2c
Grid 2b
Grid 2a
Detailed 2006
Airborne
Magnetic Survey
• A large scale NE trending
structure crossing the entire
property
• Within lower Wollaston Group
rocks in an antiformal position
and possibly thrusted.
• Graphitic conductor
• Cross-cutting magnetic
lineaments
• Shearing
• Clay alteration
• High grade Uranium boulders
5 km
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Grid 2: Gravity & DC Res Results
Grid 2: Gravity
Grid 2: DC Resistivity
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Grid 2: DC Res Section
Residual
Gravity
(mgal)
Gravity Low
Target A
900 m
Resistivity
(ohm.m)
Inverted
Resistivity
(ohm.m)
• Broad, intense gravity low (Up to 1.2 mgal)
• Two DC resistivity lows with considerable
depth extent
Coincident Gravity & DC
Resistivity Low observed
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NW Manitoba
Maguire Trend Target
Mineralization at surface suggests
open pit potential.
ƒ
Multiple gravity-resistivity targets
ƒ
Outcrop containing 9.5% U308
ƒ
Boulders in glacial till 66.3% U308
ƒ
Ground resistivity & ground gravity
survey 2012 on Maguire Trend
Priority drill target “A”
Gravity Low
indicates clay
alteration within
target area
ƒ
Structural breaks with:
ƒ
IP Chargeability
ƒ
Gravity Low ( blue zones)
ƒ
Resistivity Low
Project Comparison- Andrew Lake (+50M
lbs):
ƒ
1km
ƒ
Low gravity and low resistivity define
main alteration zone within uranium
target.
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Clay alteration around uranium zone
Comparison with Andrew Lake Deposit
How does Target A compare with Andrew Lake?
• Both have coincident gravity lows and DC resistivity lows
• Gravity lows are similar in shape
• Target A is larger in size and amplitude than the Andrew Lake anomaly
400 m
Andrew Lake
Target A
Gravity
Gravity
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Comparison with Andrew Lake Deposit
Four priority drill targets identified
Same Scale
• All have coincident gravity and DC resistivity lows
500 m
• Located adjacent to crosscutting structures
Five secondary drill targets identified
2000 m
Gravity
DC Resistivity
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Conclusion
• $6.7 M spent on exploration of the NW Manitoba Project lead to the identification of 7
major target areas and 10 defined targets
• Four year work hiatus as the Government developed a consultation framework with local
First Nations communities
• Memorandum of understanding (MOU) executed between CanAlaska and Northlands Dene
community of Lac Brochet in early 2012
• Priority Gravity – DC Resistivity drill targets defined and ready for drilling
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CanAlaska Uranium Ltd.
Thank You
www.canalaska.com
#1020-625 Howe Street
Vancouver BC, V6C 2T6
1-604-688-3211
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OTCBB: CVVUF Frankfurt: DH7N
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