EXTECH IV ATHABASCA URANIUM DEPOSIT DATABASE
Geological Survey of Canada, Saskatchewan Industry and Resources, and Alberta Geological Survey


DEPNO COUNTRY LOCATION ALLNAMES COMMODITIES
40027 Canada (Saskatchewan) 59.19.47 N -- 108.53.52 W Stewart Island Uranium Showing; Main, West, East, and Far East Zones or Lenses U

Database name: Uranium Deposits, Athabasca Basin
Custodial agency: Geological Survey of Canada
Compilers: Sunil S. Gandhi
Release date: 2007-03-02
   
Deposit name(s): Stewart Island Uranium Showing (occurrence name); Main, West, East, and Far East Zones or Lenses (occurrence name)
Political location(s): Canada; Province or state: Saskatchewan; Nearest community: Uranium city (32 km SW)
NTS map data: 074N07 (Crackingstone Penins)
Deposit clan (type): Unconformity-associated
Deposit (sub) types: Unconformity-associated - Proterozoic - clay-bound; disseminations of pitchblende and hematite, with bleached clay hallow, in sandstone 70 m above the basal unconformity; localized at two sets of fractures in a horizon rich in detrital heavy minerals; Reference: Homeniuk, L. A.; Clark, R. J. M., 1986: North Rim Deposits, Athabasca Basin; Chapter 4, Section Saskatchewan Unconformity-associated and Sedimentary-hosted Deposits of Helikian Age, In Uranium Deposits of Canada, Edited by Evans, E. L., Special Volume, The Canadian Institute of Mining and Metallurgy, The Canadian Institute of Mining and Metallurgy, 33, 323 p., p. 230 - 240
Deposit status: advanced prospect; Size category: small; Status comments: 0.066 Mt
Geologic province: Churchill - Rae Craton
Geologic subprovince: Beaverlodge Domain
Geologic district: Athabasca Basin (Northwest Rim)
Deposit object located: outcrop
Commodities: U
Mineralization styles: fracture-filling and associated dissemination; dissemination in goethite; coating; cavity - fill
Geological ages: Middle Proterozoic (host rocks)
Paleozoic (mineralization)
Tectonic setting: continental basin-intracratonic; stable; Formal name: Athabasca Basin (host rocks)
Coincident features: fracture(s) (mineralization is concentrated in two sets of fractures, trending mainly 45-50° and 145°, and dipping NW and SW, respectively); Coincident feature name: unnamed
Regional tectonic structure: normal fault (an ESE fault dipping south, along the quartzite-metapelite boundary extends below the Main zone; offsets uncoformity 20-30 m as seen in drill holes) Tectonic structure name: unnamed
Host rocks: (1) sedimentary; sandstone (quartz arenite, with heavy mineral rich beds); Depositional setting: fluviatile; Metamorphic grade: unmetamorphosed
External host rock forms:thin to thick bedded
Host rock protoliths:sandstone (fluvial sandstone; about 85 m thick in drill holes; flat-lying; unconformity with crystalline basement exposed on Stewart Island; contact trends east); Host rock protolith name: Manitou Falls Formation
Internal host rock structures:fine to very coarse grained
Individual lithologies:sandstone (well-sorted 'orthoquartzite'; detrital heavy mineral concentrations in some beds; minor interstitial calcite, chlorite and locally pitchblende, silica)
Host rock stratigraphy:Athabasca Supergroup
Country rocks: (1) granitic gneisses; (ca. 3.05 Ga old granitoids; uncoformably overlain Archean Murmac Bay Group); Country rock name: Archean Basement Complex; Metamorphic grade: amphibolite
Country rock protoliths:granitoids (Mesoarchean granitoids of the Rae craton exposed in the Beaverlodge Domain; age constraints from U-Pb zircon data on the plutonic and detrital zircons); Country rock protolith name: Archean Basement Complex
Individual lithologies:granitoids (granodiorite-tonalite suite)

(2) metasedimentary and metavolcanic rocks; (rift-type dominantly sedimentary sequence; formerly part of the Tazin Group); Country rock name: Murmac Bay Group; Metamorphic grade: amphibolite
Country rock protoliths:sandstone-siltstone-shale and volcanic rocks (polymictic conglomerate, orthoquartzite, basalts and related gabbroic and komatiitic intrusions, dolostone, iron formations, pelites and psammites); Country rock protolith name: Murmac Bay Group
Individual lithologies:paragneisses and orthogneisses (contains detrital zircons dated at 2.77 Ga; affected by 2.6-2.5 Ga and 2.36-2.28 Ga thermotectonic events; metapelite and quartzite at Stewart Island)

(3) conglomerate-sandstone; (flat-lying, undeformed, siliciclastic strata); Country rock name: Athabasca Group; Metamorphic grade: unmetamorphosed
Country rock protoliths:quartz arenite (northwest rim of the Mesoproterozoic Athabasca Group; intracratonic, dominantly siliciclastic strata; basal Manitou Falls Formation on Stewart Island); Country rock protolith name: Athabasca Group
Individual lithologies:conglomerate-sandstone-siltstone (1500 m thick; undeformed; contains detrital zircons 1.66 Ga old; overlies lateritic zone up to 50 m thick, which is not reported on Stewart Island)
Metallogenic signatures: U
Alteration signatures: hematization: hematization, late stage ; What was altered: detriral iron oxides
illite alteration: illite, massive to disseminated; What was altered: feldspars
kaolinization: kaolinite; What was altered: feldspars
silicic alteration: quartz, replacive and open space fillings; What was altered: sandstone
hydration: goethite; What was altered: iron oxides
oxidation: secondary yellow uranium minerals; What was altered: pitchblende
Mineralogy: (alteration): secondary U minerals, illite, kaolinite
(fracture fillings, coatings, disseminations): pitchblende, uraniferous goethite
(gangue minerals): hematite, calcite, quartz - secondary
(mineralization): thucholite
Radiometric ages: Object dated: Mineralogy(1); Age - Ma: 318; Dating method: U-Pb; Concentrate: whole ore; Source rock: uranium ore; Event dated: mineralization; Interpretive comment: upper intercept age of ca. 318 Ma; lower intercept at 24 Ma suggests recent reprecipitation; Reference: Homeniuk, L. A.; Clark, R. J. M., 1986: North Rim Deposits, Athabasca Basin; Chapter 4, Section Saskatchewan Unconformity-associated and Sedimentary-hosted Deposits of Helikian Age, In Uranium Deposits of Canada, Edited by Evans, E. L., Special Volume, The Canadian Institute of Mining and Metallurgy, The Canadian Institute of Mining and Metallurgy, 33, 323 p., p. 230 - 240
Deposit shape: lensoid
Deposit dimensions:length: 20 metre
width: 10 metre
thickness: 13 metre
Qualified comments: (Applies to: discovery and development) Radioactive boulders were discovered by two independent prospectors in 1955 on the south shore of Stewart Island near the southwestern tip of Crackingstone Peninsula of Lake Athabasca. The property was optioned by them to two companies, namely Frobisher Ltd. and Pipelines and Petroleum Ltd., hence a long legal dispute ensued over ownership. In the end the latter company was confirmed the owner, which became Scurry-Rainbow Oil Ltd. and in 1959-'60 the company drilled 25 holes totalling 1508 m that located the bedrock mineralization of the Main zone. The property reverted to the prospectors in 1960, and was acquired by Norex Uranium Ltd. in 1964. The company carried out mapping, trenching and drilling of 2125 m in 70 holes during 1967-'68. The work indicated resources of 22 t of U at grade averaging 0.3 % U in the Main zone. Surface work in 1967 found the West, East and East zones at displacements of 40, 135 and 600 m, respectively, from the Main zone. These three zones are smaller and untested. Additional geophysical surveys during 1979-'80 were undertaken for targets at the unconformity. In 1981 the property was owned jointly by Norex Resources Ltd. (formerly Norex Uranium Ltd.), Saskatchewan Mining Development Corp. and Eldorado Nuclear Ltd.
Links to other databases: SMDI; Key value: 1254
GSC U-Th File (Prasad); Key value: 2751
References:
Beck, L. S., 1969
Uranium Deposits of the Athabasca Region, Saskatchewan
Report, Department of Mineral Resources, Province of Saskatchewan, Department of Mineral Resources, Province of Saskatchewan, Publication code 126, 140 p., 4 maps.

Fraser, J. A., 1954
Crackingstone, Saskatchewan (Map with Marginal Notes)
Paper, Geological Survey of Canada, Publication code 54-8

Homeniuk, L. A.; Clark, R. J. M., 1986
North Rim Deposits, Athabasca Basin
Chapter 4, Section Saskatchewan Unconformity-associated and Sedimentary-hosted Deposits of Helikian Age, In Uranium Deposits of Canada, Edited by Evans, E. L., Special Volume, The Canadian Institute of Mining and Metallurgy, The Canadian Institute of Mining and Metallurgy, 33, 323 p., p. 230 - 240

Rainbird, R. H.; Stern, R. A.; Jefferson, C. W., 2002
Summary of Detrital Zircon Geochronology of the Athabasca Group, Northern Saskatchewan and Alberta
D, Section EXTECH IV Athabasca Uranium, In Summary of Investigations 2002, Volume 2, Saskatchewan Geological Survey (CD-ROM), Edited by Anonymous, Miscellaneous Report, Saskatchewan Geological Survey, Saskatchewan Industry and Resources, 2002-4.2, 371 p., 1 disks, p. 352 - 354

Saskatchewan Geological Survey, 2003
Geology, and Mineral and Petroleum Resources of Saskatchewan
Miscellaneous Report, Saskatchewan Industry and Resources, Publication code 2003-7, 173 p., 4 maps.

Saskatchewan Industry and Resources, 2001
Saskatchewan Mineral Deposits Index
Government of Saskatchewan, Geological Atlas of Saskatchewan, Internet

Tremblay, L. P., 1982
Geology of the Uranium Deposits Related to the Sub-Athabasca Unconformity
Paper, Geological Survey of Canada, Publication code 81-20, 56 p..

Resource data:
Disclaimer - Reserves/Resource Data

Her Majesty the Queen in Right of Canada, represented by the Minister of Natural Resources (NRCan) does not warrant or guarantee the accuracy, completeness or fitness for any purpose of Reserve and Resource information (Data) contained in this database, including whether the Data is compliant with any securities regulations or standards, and NRCan does not assume any liability with respect to any damage or loss incurred as a result of the use made of the Data.

Resource and reserve figures are historical in nature. The Data source provided with each set of figures should be cited if the Data are re-reported.

Estimate date: 1969; 7,400 metric ton ore; Combined with production?: no; Provisional entry?: no; Resource category: inferred
Grade-commodity information:U: 0.3 percent
weight-commodity information:U: 22 metric ton
Reference: Homeniuk, L. A.; Clark, R. J. M., 1986: North Rim Deposits, Athabasca Basin; Chapter 4, Section Saskatchewan Unconformity-associated and Sedimentary-hosted Deposits of Helikian Age, In Uranium Deposits of Canada, Edited by Evans, E. L., Special Volume, The Canadian Institute of Mining and Metallurgy, The Canadian Institute of Mining and Metallurgy, 33, 323 p., p. 230 - 240
Percent weights allocated to deposit: 100.0%

Generated 2007-03-02 2:36:44 PM with GQuery -- 3.7 ADO (3.19/3.20/3.21 -- 2006-02-24)
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