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


DEPNO COUNTRY LOCATION ALLNAMES COMMODITIES
40025 Canada (Saskatchewan) 59.18.23 N -- 107.10.05 W Fond-du-Lac Deposit; Fond-du-Lac Radioactive Boulder Train 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): Fond-du-Lac Deposit (occurrence name); Fond-du-Lac Radioactive Boulder Train (occurrence name)
Political location(s): Canada; Province or state: Saskatchewan; Nearest community: Fond-du-Lac Settlement (2 km SE)
NTS map data: 074O06 (Fond-du-lac)
Deposit clan (type): Unconformity-associated
Deposit (sub) types: Unconformity-associated - Proterozoic - clay-bound; deposit mainly in basal Athabasca sandstone; high grade core of pitchblende veins extends into basement; surrounding lower grade zone of disseminations in clay-goethite matrix; outer clay-rich halo; 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: drilled showing; Size category: small; Status comments: first drilled in 1974; more detailed drilling in 1977-'78 outlined a small deposit
Geologic province: Churchill - Rae Craton
Geologic subprovince: Beaverlodge Domain
Geologic district: Athabasca Basin (North Rim)
Deposit object located: outcrop
Commodities: U
Mineralization styles: fracture-filling and associated dissemination; dissemination in goethite; coating; cavity - fill; remobilized ore
Geological ages: Middle Proterozoic (host rocks)
Late Mesoproterozoic - Phanerozoic (mineralization)
Tectonic setting: continental basin-intracratonic; stable; Formal name: Athabasca Basin (host rocks)
Coincident features: fracture(s) (higher grade zone controlled mainly by stockwork of fractures; surrounded by lower grade zone of mainly disseminated, and in part remobilized uranium); Coincident feature name: northeast-trending fracture zone
paleoregolith
Regional tectonic structure: fracture zone (mineralization in a stockwork of steeply dipping fractures comprising a zone trending 050°; in the sandstone; a few fractures extend into the basement) Tectonic structure name: steep northeast fracture zone
Host rocks: (1) metamorphic; metasedimentary schist (meta-arkose and metapelites); Depositional setting: platform-shelf; Metamorphic grade: granulite; Component: basement at unconformity
External host rock forms:schistose-gneissic metasediments
Host rock protoliths:arkosic sandstone and pelitic sediments (drill holes show mainly meta-arkose below the deposit, metapelites to the northeast and a northwesterly zone of faulting and alteration between them); Host rock protolith name: Murmac Bay Group
Internal host rock structures:medium to coarse grained
Individual lithologies:meta-arkose (U-Pb zircon age of 2864 ± 300 Ma on granulitic meta-arkosic unit consistent with Murmac Bay Group)
metapelite (lower metamorphic grade metapelites may be younger)
Host rock stratigraphy:Murmac Bay Group

(2) surficial; laterite (10-15 m thick; thin bleached clayey zone at top, thick red hematitic and green chloritic zones below); Host series: paleoregolith; Depositional setting: subaerial; Metamorphic grade: unmetamorphosed; Component: basement at unconformity
External host rock forms:lateritic profile
paleoregolith
Host rock protoliths:arkosic sandstone and pelitic sediments (lateritic profile is thicker at the mineralized fracture zone that extends from sandstone into the basement; uranium deposition in the bleached zone); Host rock protolith name: Murmac Bay Group
Internal host rock structures:saprolitic
Individual lithologies:laterite (mainly meta-arkose beneath the mineralized zone; metapelites to the northeast)
Host rock stratigraphy:Sub-Athabasca Group Paleosol

(3) sedimentary; sandstone-conglomerate (30 m thick at the deposit; mainly sandstone with minor siltstone, shale and basal conglomerate); Depositional setting: fluviatile; Metamorphic grade: unmetamorphosed; Component: main mineralized zone
External host rock forms:thin to thick bedded
Host rock protoliths:sandstone-siltstone-shale (basal congloerate bed variable in thickness; siltstone and shale occur as discontinuous layers intercalated with medium grained sandstone); Host rock protolith name: Manitou Falls Formation
Internal host rock structures:crossbedding
Individual lithologies:sandstone (sandstone dominant; white to beige, medium grained; nearly flat-lying; the main host of the uranium mineralization at the deposit)
conglomerate
mudstone
Host rock stratigraphy:Manitou Falls Formation
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 (upper) - granulite
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; meta-arkose and metapelites at Fond-du-Lac)

(3) conglomerate-sandstone; (flat-lying, undeformed, siliciclastic strata); Country rock name: Athabasca Group; Metamorphic grade: unmetamorphosed
Country rock protoliths:quartz arenite (north rim of the Mesoproterozoic Athabasca Group; intracratonic, dominantly siliciclastic strata; basal Manitou Falls Formation in Fond-du-Lac area); 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; thinner at Fond-du-Lac but profile typical)
Metallogenic signatures: U
Alteration signatures: hematization: hematite; What was altered: iron oxides, mafic silicates
carbonate alteration: calcite; What was altered: calcic minerals
hydration: goethite; What was altered: iron oxides
silicic alteration: quartz, replacive and open space fillings; What was altered: host rocks
kaolinization: kaolinite; What was altered: silicate minerals
oxidation: secondary yellow uranium minerals; What was altered: pitchblende
reprecipitation by ground water: extension of low grade zone to the west; What was altered: pitchblende, earlier uranium cncentrations
Mineralogy: (veins and disseminations / main mineralized zone): pitchblende
(veins and disseminations / mineralization zone): coffinite, uraniferous goethite
(veins and disseminations / mineralization): hematite
(veins and disseminations / mineralization zone): calcite, quartz - secondary
(veins and disseminations / main mineralized zone): carbon buttons
Radiometric ages: Object dated: Mineralogy(1); Age - Ma: 1,200; -100; Dating method: U-Pb; Concentrate: whole ore; Source rock: uranium ore (high grade); Event dated: mineralization (early); Interpretive comment: initial mineralization age range: 1200-1100 Ma; remobilization or recrystalliztion at 215 and 80 Ma; 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: lens, high grade core
Deposit dimensions:length: 390 metre
width: 75 metre
thickness: 40 metre
Qualified comments: (Applies to: discovery and development) An airborne radiometric survey was conducted by Mokta (Canada) Limited for Famok Limited in 1967. Followup ground work in 1968 led to the discovery of uraniferous boulder train 10 km long, about 1 km wide, trending 255° in 10 m thick till. Its bedrock source was found in 1969. Deposit was outlined in 1970 by 2245.5 m drilled in 35 drill holes on a 650 m grid. Resources were reported in 1970 based on the detailed drilling: 381 t U in 180000 t ore averaging 0.212 % U at a cut-off grade of 0.05 % U. Furtherr exploration in the area was undertaken by Eldorado Nuclear Limited during 1975-1978. The company carried out detailed drill program of 350 holes spaced every 10 m along lines 20 m apart. The inner high grade zone trends about 235°, and is approximately 390x75m in plan and up 10 to 40 m in height. The surrounding low grade zone is about 30 m wide, but to the west it is as much as 150 wide.

(Applies to: mineralization) A relatively hig grade core is surrounded by an irregularly shaped low grade mineralization. The core zone has pitchblende veins along steeply dipping fractures that form a stockwork trending northeast. A few of the veins extend into the basement. The veins are commonly less than 1 mm wide, and contain gangue minerals quartz, hematite, limonite (goethite) and carbonate (siderite). Some coffinite and pyrite are present. The altered host sandstone is dark red and silicified.Toward the edge of the core zone it is grey to white, porous, clay altered, and contains rare carbon buttons. In the low grade zone uranium favours coarse, porous and cross-bedded parts of sandstone that are rich in interstitial clay. A weak white-clay alteration present locally at the unconformity in chloritic paleosol may be related to mineralization.
Links to other databases: SMDI; Key value: 1572
GSC U-Th File (Prasad); Key value: 2883
References:
Homeniuk, L. A.; Clark, R. J. M.; Bonnar, R., 1982
The Fond-du-Lac Uranium Deposit
Bulletin of the Canadian Institute of Mining and Metallurgy, Volume 75, p. 84 - 89

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: 1970; 0.18 million metric tons ore; Combined with production?: no; Provisional entry?: no; Resource category: probable reserve
Grade-commodity information:U: 0.212 percent
Cutoff grade-commodity:U: 0.05 percent
weight-commodity information:U: 381 metric ton
Reference: Homeniuk, L. A.; Clark, R. J. M.; Bonnar, R., 1982: The Fond-du-Lac Uranium Deposit; Bulletin of the Canadian Institute of Mining and Metallurgy, Volume 75, p. 84 - 89
Percent weights allocated to deposit: 100.0%

Generated 2007-03-02 2:36:14 PM with GQuery -- 3.7 ADO (3.19/3.20/3.21 -- 2006-02-24)
GlobalDB System, Geological Survey of Canada, Natural Resources Canada