Database name: |
Uranium Deposits, Athabasca Basin |
Custodial agency: |
Geological Survey of Canada |
Compilers: |
Sunil S. Gandhi |
Release date: |
2007-03-02 |
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Deposit name(s): |
Collins Bay A Uranium Deposit (mine name) |
Political location(s): |
Canada; Province or state: Saskatchewan; Nearest community: Rabbit Lake mine-mill complex (10.5 km N 26° E) |
NTS map data: |
064L05 (Cunning Bay) |
Deposit clan (type): |
Unconformity-associated |
Deposit (sub) types: |
Unconformity-associated - Proterozoic - clay-bound; Polymetallic deposit containing significant amounts of Ni, Co and As; hosted by clay altered paleoregolith under a remnant of Athabasca sandstone on the hanging wall of NE-trending Collins Bay thrust ; Reference: 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.. |
Deposit status: |
past producer; Size category: medium; Status comments: Open pit; ore body mined out during 1995-'97. |
Geologic province: |
Churchill - Hearne Craton |
Geologic subprovince: |
Wollaston Domain (Fold Belt) |
Geologic district: |
Eastern Athabasca Basin |
Deposit object located: |
outcrop |
Commodities: |
U; Ni; Co; As; Au; Ag; Gf; Pb; Fe |
Mineralization styles: |
massive mineralization (main mineralized zone); disseminated; nodular; irregular aggregation; veins and stringers |
Geological ages: |
Middle Mesoproterozoic (mineralization) |
Tectonic setting: |
continental marginal deformation zone-fold belt; convergent; Formal name: Wollaston Fold Belt (host rocks) continental basin-unconformity; stable; Formal name: sub-Athabasca regolith (alteration) continental basin-intracratonic; stable; Formal name: Athabasca Basin (host rocks) continental fault zone-reverse faulting; transpressive; Formal name: Collins Bay thrust fault (mineralization) |
Coincident features: |
unconformity (mineralization straddles the unconformity; mainly within paleoregolith; extends into basement); Coincident feature name: Sub-Athabasca unconformity fault zone (post-Athabasca thrust; 030° trend; dip 30-50° to SE; vertical displacement 15-20 m; edges of ore zone in footwall sandstone); Coincident feature name: Collins Bay Fault |
Regional tectonic structure: |
thrust zone(s) (a thrust fault dipping moderately to the east-southeast; with a small displacement post-dating the Athabasca Group, localized the mineralization ) Tectonic structure name: Collins Bay Fault Zone |
Host rocks: |
(1) metamorphic; metasedimentary schist (graphitic metapelite); Depositional setting: shallow marine; Metamorphic grade: amphibolite (upper) - granulite; Component: basement at unconformityExternal host rock forms: | beds and lenses | Host rock protoliths: | pelite and semipelite (in fault contact with Collins Bay granitoid dome to the west; elsewhere disconformably overlies granitoid basement); Host rock protolith name: unit of Upper Wollaston Supergroup semipelite | Internal host rock structures: | foliated | Individual lithologies: | biotitic gneiss (biotitic quartzo-feldspathic gneiss on the hangingwall of the Collins Bay thrust; includes small pegmatitic bodies) graphitic metapelite (graphite-rich biotite-quartz-feldspar gneiss and schist; base approximately 25 m above the Collins Bay thrust) | Host rock stratigraphy: | Upper Wollaston Supergroup |
(2) surficial; laterite (weathered basement; profile ~30 m deep); Host series: paleoregolith; Depositional setting: subaerial; Metamorphic grade: unmetamorphosed; Component: basement at unconformityExternal host rock forms: | lateritic profile | Host rock protoliths: | metasedimentary schist and gneiss (paleoweathered zone overprinted by strong clay alteration related to uranium mineralization ); Host rock protolith name: Wollaston Supergroup | Internal host rock structures: | lateritic zonation | Individual lithologies: | laterite (paleoregolith well developed on paragneiss; granitoid gneiss shows little paleoweathering) | Host rock stratigraphy: | Sub-Athabasca Group Paleosol |
(3) sedimentary; sandstone (unconformably overlying crystalline basement); Depositional setting: fluviatile; Metamorphic grade: unmetamorphosed; Component: above unconformityExternal host rock forms: | thin to thick bedded, flat lying | Host rock protoliths: | quartz arenites (basal unit of Athabasca Group; sandstone and pebbly sandstone with conglomerate at base); Host rock protolith name: Manitou Falls Formation | Internal host rock structures: | mainly medium-grained to granule; cross-bedded | Individual lithologies: | quartz arenite (minor quartz and clay matrix; up to 25 m thickn on footwall side of Collins Bay thrust; a small remnant to the east above ore zone ) | Host rock stratigraphy: | Athabasca |
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Country rocks: |
(1) granitoid gneiss; (reactivated Archean granites); Country rock name: Collins Bay Granitoid Dome; Metamorphic grade: amphibolite - upperCountry rock protoliths: | granitic plutons (Archean granitic plutons; in fault contact with paragneisses to the east in northeast-trending tight folds); Country rock protolith name: Collins Bay Granitoid Dome | Individual lithologies: | granitoids (mainly granite to granodiorite) |
(2) metasedimentary rocks; (folded and metamorphosed sediments; deposited in late foreland basin of the Trans-Hudson orogen; Hidden Bay assemblage of earlier literature); Country rock name: Upper Wollaston Supergroup ; Metamorphic grade: amphibolite (upper) - granuliteCountry rock protoliths: | sandstone-mudstone-carbonate (deposited in shallow, marine, near-shore environment of late foreland basin of Trans-Hudson orogen); Country rock protolith name: Upper Wollaston Supergroup siltstone; Country rock protolith name: Lower Wollaston Supergroup | Individual lithologies: | quartzitic, pelitic, mafic gneisses (includes graphitic meta-pelites) |
(3) sandstone-conglomerate; (continental siliciclastic sediments ); Country rock name: Athabasca Group; Metamorphic grade: unmetamorphosedCountry rock protoliths: | conglomerate-sandstone (basal conglomerate and sandstone units; deposited on lateritic paleosol); Country rock protolith name: Manitou Falls Formation | Individual lithologies: | sandstone (basal conglomerate, overlain by massive conglomerate with sandy layers and shale partings) |
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Metallogenic signatures: |
U-Ni-As-Au-Ag |
Alteration signatures: |
argillic alteration: multi-colored illitic clay-rich mass, graphitic; What was altered: sub-Athabasca regolith; Component: mineralization zone hematization: disseminated fine hematite; red colouration; What was altered: metasediments, paleoregolith, sandstone; Component: mineralization zone chlorite alteration: green coloration due to chlorite; What was altered: metasediments |
Mineralogy: |
(disseminated mineralization): pitchblende - sooty, coffinite (irregular aggregation): pitchblende - massive (massive ore): pitchblende - massive, pitchblende - sooty, coffinite, kasolite, niccolite, rammelsbergite, pararammelsbergite, galena, sphalerite (nodular ore): pitchblende - massive, coffinite (veins and stringers / late stage mineralization): pitchblende - late stage |
Radiometric ages: |
Object dated: Mineralogy(1); Age - Ma: 1,379; +6; -6; Dating method: U-Pb; Concentrate: pitchblende; Source rock: uranium ore; Formal name: initial mineralization event; Event dated: mineralization (early); Interpretive comment: 4 fractions from one sample area; 5 from another area gave 1349±15 Ma; lower intecepts 550-650 Ma; Reference: Cumming, G. L.; Krstic, D., 1992: The Age of Unconformity-Related Uranium Mineralization in the Athabasca Basin, Northern Saskatchewan; Canadian Journal of Earth Sciences, Volume 29, p. 1623 - 1639
Object dated: Alteration Signature(1); Age - Ma: 1,266; +39; -39; Dating method: K-Ar; Concentrate: whole rock; Source rock: clay-hematite alteration zone; Formal name: main mineralization event; Event dated: alteration (hypogene); Interpretive comment: illitic (sericitic) and chloritic clay associated with high grade zone; age close to pitchblende age; Reference: 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.. |
Deposit shape: |
lensoid; Component: main mineralized zoneDeposit dimensions: | long axis: 50 metre short axis: 34 metre thickness: 13 metre |
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Qualified comments: |
(Applies to: discovery and development) During 1970 exploration crews of Gulf Minerals Canada Limited carried out followe-up work on an airborne EM anomay that led to the discovery of a well-defined train of mineralized boulders. This 2.4 km long and 45 m wide train was traced north to the waters of Collins Bay of Wollaston Lake. Ground geophysical surveys early in 1971 defined the drill targets under water. Diamond drilling later in the year located the deposit under 14 m of water and 7 m of glacial till. The core recovery was poor due to high clay content. Hence in 1976 reverse circulation drilling was done at 7.6 m grid pattern to delineate the orebody. Dykes were built in 1994 for open pit mining, which was carried out during 1995-'96. The high grade boulders in the glacial train constituted the overburden ore.
(Applies to: mineralization) The mineralized zone comprises a high grade core and a low grade envelope. The orebody is enclosed in illitic clay, which contains large amounts of graphite. The deposit is located at the sub-Athabasca Group unconformity in a zone of imbricate faulting associated with the north-northeast trending Collins Bay thrust fault. Boundaries of the clay zone are fault controlled, with basement paragneisses on the southeast side and the Athabasca sandstone on the other side. The core zone has grades up to 70.6 % U over 2.3 m. The nickel assays are up to 20 % over 1.5 m. The nickel high values occur below the massive uranium mineralization. The deposit also contains significant amounts of cobalt, silver and gold. |
Links to other databases: |
SMDI; Key value: 0617 |
Geophysical-chemical signature: |
Signature type: Airborne Radiometrics; Response type: positive (moderate) Signature type: Ground EM; Response type: positive (strong) |
References: |
Bennett, R. W., 2002 |
Geological Atlas of Saskatchewan, Version 5 (2002) |
Government of Saskatchewan, CD-ROM |
Jones, B., 1980 |
Geology of the Collins Bay Uranium Deposits |
Bulletin of the Canadian Institute of Mining and Metallurgy, Volume 73, p. 84 - 90 |
Prasad, N., 2002 |
Uranium File: Canmindex |
Geological Survey of Canada, Canadian Mineral Occurrence Index (Canmindex), CD-ROM |
Renaud, A., 2006 |
Unconformity and Basement-hosted Uranium deposits at the Rabbit Lake Operations, Collins Bay, Saskatchewan |
C, Section Athabasca Basin Uranium Deposits, In Abstracts Volume for the 2006 CIM Uranium Field Conference, September 11-12, Saskatoon; Uranium: Athabasca Deposits & Analogues, Edited by Quirt, D., Abstracts Volume, Canadian Institute of Mining and Metallurgy, Saskatoon Section, CIM Geological Society, 164 p., p. 1 - 3 |
Ruzicka, V., 1986 |
Uranium Deposits in the Rabbit Lake - Collins Bay Area, Saskatchewan |
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. 144 - 154 |
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 |
Thomas, D. J.; Mathews, R. B.; Sopuck, V., 2000 |
Athabasca Basin (Canada) - Unconformity-type Uranium Deposits: Exploration Model, Current Mine Development and Exploration Directions |
In Geology and Ore Deposits 2000: the Great Basin and Beyond; May 15 - 18, 2000 Symposium Proceedings (CD-ROM), Edited by Cluer, J. K.; Price, J. G.; Struhsacker, E. M.; Hardyman, R. F.; Morris, C. L., Symposium Proceedings, Geological Society of Nevada, Geological Society of Nevada, Reno, Nevada, 647 p., p. 103 - 126 |
Thomas, D. J.; Jefferson, C. W.; Card, C.; Yeo, G.; Sopuck, V., 2002 |
Introduction: the Eastern Athabasca Basin and its Uranium Deposits |
Chapter 1, In Field Trip A1: the Eastern Athabasca Basin and its Uranium Deposits, May 24-26, 2002, GAC-MAC Saskatoon 2002, Edited by Andrade, N; Breton, G.; Jefferson, C. W.; Thomas, D. J.; Tourigny, G.; Wilson, S.; Yeo, G. M., Field Guide Book, Geological Association of Canada - Mineralogical Associationof Canada, Geological Association of Canada, 102 p., p. 1 - 22 |
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.. |
Ward, D. M., 1989 |
Rabbit Lake Project - History of Exploration and General Geology |
Bulletin of the Canadian Institute of Mining and Metallurgy, Volume 82, p. 40 - 48 |
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Production data: |
Report period: from 1995 until 1997; 134,600 metric ton ore; Provisional entry?: yes; Yearly or summary?: SGrade-commodity information: | U: 4.83 percent | weight-commodity information: | U: 6,500 metric ton | Reference: Ward, D. M., 1989: Rabbit Lake Project - History of Exploration and General Geology; Bulletin of the Canadian Institute of Mining and Metallurgy, Volume 82, p. 40 - 48 Percent weights allocated to deposit: 0.0% |
Associated mine(s): |
Collins Bay A Zone Uranium Mine (40002) |