CANADIAN AND WORLD MINERAL DEPOSIT DATABASES
Geological Survey of Canada


 
Database name: World Fe-oxide+/-Cu-Au-U (IOCG) deposits
Compilers: Sunil S. Gandhi
Release date: 2015-03-03
   
Deposit name(s): Lake; Texada Mines-Lake
Longitude / Latitude: -124.52694 / 49.70278
Political location(s): Canada; Province or state: British Columbia; Nearest community: Vancouver (115 km NW)
NTS map data: 092F10 (Comox)
Deposit clan (type): Iron Skarn-type
Deposit (sub) types: massive magnetite pods in skarns replacing mainly volcanic host rocks; northern part of the ore body nearest to limestone is richer in sulphides, which are believed to be coeval with magnetite; Reference: Sangster, D. F., 1969: The Contact Metasomatic Magnetite deposits of Southwestern British Columbia; Bulletin, Geological Survey of Canada, Geological Survey of Canada, Department of Energy, Mines and Resources, Ottawa, Canada, Publication code 172, 85 p., 9 maps.
Deposit status: past producer; Size category: small
Geologic province: Cordilleran Orogen
Geologic subprovince: Insular Belt
Geologic district: Wrangell Terrane
Deposit object located: open pit
Commodities: Fe; Cu; Au; Ag
Mineralization styles: massive magnetite lenses
Geological ages: Late Triassic - Early Jurassic (host rocks)
Early Jurassic - Middle Jurassic (mineralization)
Tectonic setting: continental marginal arc-fold belt; transpressive; Formal name: Bonanza magmatic arc (mineralization)
Coincident features: limestone-mafic volcanic contact (skarn mineralization in andesite of an overturned south limb of a syncline, near limestone below); Coincident feature name: Quatsino Formation-Karmutsen volcanic boundary
Regional tectonic structure: northwest-trending open folds (early Jurassic to late Cretaceous; limestone and underlying volcanics folded into north plunging folds) Tectonic structure name: Coast Range orogeny
northwest-trending major faults (the faults controlled the emplacement of some Jurassic intrusions and the associated skarn mineralization) Tectonic structure name: Ideal and Holly faults
Host rocks: (1) volcanic; mafic-intermediate volcanic rocks (basaltic to andesitic flows); Magma series/sedimentary package/metamorphic group: calc-alkaline; Depositional setting: shallow marine; Metamorphic grade: greenschist
External host rock forms:flows, tuffs and agglomerate
Host rock protoliths:basalt-andesite (flows, some pillowed; folded and altered near the desposit; deposit 365 m from related Gillies intrusion/stock); Host rock protolith name: Karmutsen Group
Internal host rock structures:massive to porphyritic
Individual lithologies:andesite-basaltic andesite (faint bedding in tuffaceous beds; clouding of plagioclase and growth of actinolite in hornblende)
Host rock stratigraphy:Karmutsen Group

(2) sedimentary; carbonate (limestone completely recrystallized to medium grained marble); Magma series/sedimentary package/metamorphic group: carbonate; Depositional setting: shallow marine; Metamorphic grade: greenschist
External host rock forms:well bedded
Host rock protoliths:carbonate (conformably overlies mafic flows of the Karmutsen Group that forms lower part of the Vancouver Group); Host rock protolith name: Quatsino Formation of Vancouver Group
Internal host rock structures:white and grey beds; some thin dark grey beds
Individual lithologies:marble (medium grained; folded, recrystallized and intruded by quartz monzonitic Gillies stock)
Host rock stratigraphy:Quatsino/Marble Bay Formation
Related igneous rocks: (1) intrusive; quartz monzonite-monzogabbro suite (deposit genetically related to the intrusion); Initials: Gillies Intrusion/Stock; Magma series: calc-alkaline; Depositional setting: continental
Individual lithologies:quartz monzonite (older phase massive grey, younger phase massive to porphyritic, and the yongest aplitic dykes)

(2) intrusive; gabbro-diorite suite (post-ore dykes, up to 15 m wide); Initials: Feldspar Porphyry dykes; Magma series: calc-alkaline; Depositional setting: continental
Individual lithologies:porphyritic diorite (phenocrysts of plagioclase, 15 -20 %, and pyroxene, 2 %, in groundmass of plagioclase, hornblende, apatite, sericite and epidote)
Metallogenic signatures: Fe-Cu-Au-Ag
Alteration signatures: skarn: andraditic garnet and diopsidic clinopyroxene; What was altered: andesite
Mineralogy: (alteration): garnet, garnet, diopside-hedenbergite, epidote
(gangue): calcite
(mineralization): magnetite, chalcopyrite, pyrite, pyrrhotite, arsenopyrite, sphalerite, actinolite
Radiometric ages: Object dated: Related igneous rocks(1); Age - Ma: 176; +2; -2; Dating method: U-Pb; Concentrate: zircon; Source rock: quartz monzodiorite; Formal name: Gillies Intrusion; Event dated: intrusive event; Interpretive comment: age marks the time of formation of Fe skarn 365 m northeast of the intrusion in volcanic rocks; Reference: Ettlinger, A. D.; Ray, G. E., 1990: Precious Metal Enriched Skarns in British Columbia: An Overview and Geological Study; Paper, Geological Survey Branch, Mineral Resources Division, British Columbia Ministry of Energy, Mines and Petroleum Resources, Province of British Columbia, Canada, Publication code 1989-3, 128 p., 1 maps.
Deposit shape: lensoid
Deposit dimensions:long axis: 150 metres
width: 50 metres
depth: 75 metres
Qualified comments: (Applies to: discovery and development) From 1901 to 1921, 35 955 grams of silver and 3 017 grams of gold were recovered from 946 tonnes; sulphides more abundant in northern part of the deposit near limestone; a chalcopyrite lens 20x0.75 m. Combined production during 1952-1956 from Prescott, Paxton, Lake and Lake Extension open pit and underground mines: 1 997 313 t ore mined, 1 989 996 t ore milled, with recovery of 1 300 466 116 kg Fe.
Links to other databases: BC MINFILE; Key value: 092F 259
References:
British Columbia Mines and Energy, 2001
British Columbia MINFILE Database
Government of British Columbia, MINFILE Mineral Inventory, Internet

Carson, D. J. T.; Muller, J. E.; Wanless, R. K.; Stevens, R. D., 1971
Age of the Contact Metasomatic Copper and Iron Deposits, Vancouver and Texada Islands, British Columbia
Paper, Geological Survey of Canada, Geological Survey of Canada, Department of Energy, Mines and Resources, Ottawa, Canada, Publication code 71-36, 9 p.

Ettlinger, A. D.; Ray, G. E., 1990
Precious Metal Enriched Skarns in British Columbia: An Overview and Geological Study
Paper, Geological Survey Branch, Mineral Resources Division, British Columbia Ministry of Energy, Mines and Petroleum Resources, Province of British Columbia, Canada, Publication code 1989-3, 128 p., 1 maps.

Ray, G. E.; Ettlinger, A. D.; Meinert, L. D., 1990
Gold Skarns: Their Distribution, Characteristics and Problems in Classification
Section Mineral Deposit Studies, in Geological Fieldwork 1989: A Summary of Field Activities and Current Research, Edited by Anonymous, Paper, Geological Survey Branch, Mineral Resources Division, British Columbia Ministry of Energy, Mines and Petroleum Resources, Province of British Columbia, Canada, 1990-1, 535 p, p. 237 - 246

Sangster, D. F., 1969
The Contact Metasomatic Magnetite deposits of Southwestern British Columbia
Bulletin, Geological Survey of Canada, Geological Survey of Canada, Department of Energy, Mines and Resources, Ottawa, Canada, Publication code 172, 85 p., 9 maps.

Webster, I. C. L..; Ray, G. E., 1990
Geology and Mineral Deposits of Northern Texada Island (92F/9, 10 and 15)
Section Mineral Deposit Studies, in Geological Fieldwork 1989: A Summary of Field Activities and Current Research, Edited by Anonymous, Paper, Geological Survey Branch, Mineral Resources Division, British Columbia Ministry of Energy, Mines and Petroleum Resources, Province of British Columbia, Canada, 1990-1, 535 p, p. 257 - 265


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