1 KEGS- EXPLORATION 07 SYMPOSIUM GEOPHYSICAL CONTRIBUTIONS TO NEW DISCOVERIES Synthetic Model Testing and Titan-24 DC Resistivity Results at Wheeler River An Athabasca-type Unconformity Uranium Target in Northwestern Saskatchewan, Canada By: Jean M. Legault*, Quantec Geoscience Ltd., Toronto, ON Don Carriere, Carriere Process Management Ltd., Mississauga, ON Larry Petrie, Denison Mines Corporation, Saskatoon, SK
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Synthetic Model Testing and Titan-24 DC Resistivity Results at Wheeler River
Synthetic Model Testing and Titan-24 DC Resistivity Results at Wheeler River. An Athabasca-type Unconformity Uranium Target in Northwestern Saskatchewan, Canada. - PowerPoint PPT Presentation
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KEGS-EXPLORATION 07
SYMPOSIUMGEOPHYSICAL
CONTRIBUTIONS TO NEW
DISCOVERIES
Synthetic Model Testing and Titan-24 DC Resistivity Results at Wheeler River
An Athabasca-type Unconformity Uranium Target in Northwestern Saskatchewan, Canada
By: Jean M. Legault*, Quantec Geoscience Ltd., Toronto, ONDon Carriere, Carriere Process Management Ltd., Mississauga, ON
Larry Petrie, Denison Mines Corporation, Saskatoon, SK
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KEGS-EXPLORATION 07
SYMPOSIUMGEOPHYSICAL
CONTRIBUTIONS TO NEW
DISCOVERIES
Wheeler River Case History
• Survey design based on initial synthetic model testing (best approach)
• Comparison of several array configurations(modeling and field application)
• Presence of major powerline impacts geophysics(choice of methods)
• Compare 2-D and 3-D Inversion results(improve understanding)
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KEGS-EXPLORATION 07
SYMPOSIUMGEOPHYSICAL
CONTRIBUTIONS TO NEW
DISCOVERIES
Titan 24 DCIP & MT
Overview
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KEGS-EXPLORATION 07
SYMPOSIUMGEOPHYSICAL
CONTRIBUTIONS TO NEW
DISCOVERIES
Common DCIP Electrode Arrays
Titan PldpdpCombinesPldp-left + Pldp-right
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KEGS-EXPLORATION 07
SYMPOSIUMGEOPHYSICAL
CONTRIBUTIONS TO NEW
DISCOVERIES
Standard Titan spreadN=0.5 to 23.5, a= 100m(552 data points)
Line Length 2.4 kmCurrent Injectionsinside Rx Array
N=0.5
N=23.5
Extended Titan spread(adding current extensionsbeyond end of receiver array)N=0.5-33.5, a=100m(approx. 1032 points)
Line Length approx. 4.4 kmCurrent Injections inside
& outside Rx Array
N=0.5
N=23.5
N=10.5
N=33.5
Titan-24 Pole-Dipole-Dipole Pseudosections
TITAN DCIP ARRAY CONFIGURATIONS
Note: Combinespldp & dppl data
Note: Combinespldp & dppl data
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KEGS-EXPLORATION 07
SYMPOSIUMGEOPHYSICAL
CONTRIBUTIONS TO NEW
DISCOVERIES
Case History: M-zone at Wheeler River
Commissioned byDenison Mines Corporation
in JV with Cameco Corporationand Japan-Canada Uranium Ltd.
April-May, 2007
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KEGS-EXPLORATION 07
SYMPOSIUMGEOPHYSICAL
CONTRIBUTIONS TO NEW
DISCOVERIES
• Define DC (+/- IP) signatures associated with:a) Uranium-bearing graphitic conductor at M-Zoneb) Granitic gneiss to the south-east of M-Zonec) Alteration chimney in sandstones above M-Zone
• Wheeler River mineralization occurs in 400m thick Athabasca Sandstone along the Unconformity, below alteration zone that is associated with underlying basement Graphitic metapelites known as the M-Zone conductive trend.
• Test Titan multi-parameter capability, with emphasis onGalvanic DC Resistivity (possibly also IP) using Pole-Dipole Array, in direct comparison with Dipole-Dipole and more widely used Pole-Pole Array.
Titan Survey Objectives
• Field Surveys were preceded by 2-D synthetic modeling study that tested for optimal array parameters (dipole size) and configurations (Pldp vs Plpl vs Dpdp array).
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KEGS-EXPLORATION 07
SYMPOSIUMGEOPHYSICAL
CONTRIBUTIONS TO NEW
DISCOVERIES
Introduction
Wheeler River Project
Key Lake
Moore Lake
WheelerRiverLocation:
HISTORIC NOTES
Since 1980’s, major powerline through property (along BL) – impacts EM follow-up.
Originally discovered in 1980’s (UTEM follow-up of Airborne) but remained unexplored until recently.
35km NE of Key Lake & 10km W of Moore Lake.
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KEGS-EXPLORATION 07
SYMPOSIUMGEOPHYSICAL
CONTRIBUTIONS TO NEW
DISCOVERIES
BASEMENT AND UNCONFORMITY HOSTED URANIUM DEPOSIT STYLES
ALTERATION ASSOCIATED WITH UNCONFORMITY-HOSTED URANIUM DEPOSITS
WHEELER M-ZONE – 3-D VOLUME of 2-D SMOOTH DC RESISTIVITY
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KEGS-EXPLORATION 07
SYMPOSIUMGEOPHYSICAL
CONTRIBUTIONS TO NEW
DISCOVERIES
Z=20mZ=100m
Note: PL+Road+NoiseVisible in Near Surface
Z=300m
Note: Alteration in IP low above UC?
WHEELER M-ZONE – 3-D VOLUME of 2-D SMOOTH CHARGEABILITY
Z=500m
Note: Graphite IP High?
Z=700m
Note: Graphite IP High?
Z=900m
Note: Graphite IP High?
Z=1100m
Note: Graphite IP High?
Z=1400m
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KEGS-EXPLORATION 07
SYMPOSIUMGEOPHYSICAL
CONTRIBUTIONS TO NEW
DISCOVERIES
WHEELER M-ZONE – 3-D VOLUME of 3-D SMOOTH RESISTIVITY
Z=20mZ=100m
Note: Powerline correlateswith near surface DC low
Z=300m
Note focused DC resistivitylow 100m above UC
Z=500m
Note: Graphite wellresolved in basement
Z=900m
Note: Absence of NWmigration in Gp signature
Z=1300m
Note: Absence of NWmigration in Gp signature
Z=1400m
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KEGS-EXPLORATION 07
SYMPOSIUMGEOPHYSICAL
CONTRIBUTIONS TO NEW
DISCOVERIES
WHEELER M-ZONE – 3-D VOLUME of 3-D SMOOTH CHARGEABILITY
Z=200mZ=100m
Note: Layer-like IP-High zone in sandstone?
Z=300m
Note widespreadpresence of IP highlayer in sandstone
Z=500m
Note: Well definedIP high along DC low
(except on north lines)
Z=900m
Note: Well definedIP high along DC low(also on north lines)
Z=1300m
Note: Well definedIP high along DC low(also on north lines)
Z=1400m
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KEGS-EXPLORATION 07
SYMPOSIUMGEOPHYSICAL
CONTRIBUTIONS TO NEW
DISCOVERIES
Study Findings
• Field surveys corroborated our initial 2-D DC synthetic modeling studies, i.e., Dpdp offered best resolution but poorest penetration; Plpl had greatest penetration but poorer resolution; Pldp had better combination of resolution, penetration and economy.
• MT data quality excellent – not hindered by ground contacts or Powerline effects – confirms all season capability.
• DC resistivity data quality and survey productivity greatly improved current injections (>0.5A avg), thanks to more powerful GDD Tx – suggests >2-3 season capability for DC/IP.
• Multi-parameter DC-IP-MT results show remarkable similarities and contrasting behaviour (i.e., DC vs MT; 2D vs 3D).
• DC resistivity results do not appear to be significantly hindered by powerline effects, but IP significantly more affected (acceptable).
• Coincident DC+MT resistivity low and IP high confirmed over graphite > additional tool for geologic mapping & discrimination.
• 3-D inversions simplify, improve understanding of responses.