GEOSCAN Search Results: Fastlink


TitleGeochemical and geochronological discrimination of biotite types at the Detour Lake Gold Deposit, Canada
AuthorDubosq, R; Schneider, D A; Camacho, A; Lawley, C J M
SourceMinerals vol. 9, no. 10, 596, 2019 p. 1-22, Open Access logo Open Access
Alt SeriesNatural Resources Canada, Contribution Series 20190561
Mediapaper; on-line; digital
File formatpdf; html
ProvinceOntario; Quebec
NTS31M; 31N; 31O; 32B; 32C; 32D; 32E; 32F; 32G; 32J; 32K; 32L; 41P; 42A; 42H; 42I
AreaRouyn-Noranda; Timmins; Detour Lake; Chibougamau
Lat/Long WENS -82.0000 -74.0000 50.5000 47.5000
Subjectseconomic geology; geochemistry; geochronology; Science and Technology; Nature and Environment; mineral deposits; gold; mineralization; ore mineral genesis; biotite; amphibolite facies; tectonic setting; radiometric dating; argon argon dating; veins; foliation; titanium geochemistry; magnesium geochemistry; Archean; Detour Lake Deposit; Superior Province; Paleoproterozoic; Neoarchean; Precambrian; Proterozoic
Illustrationslocation maps; geoscientific sketch maps; photographs; photomicrographs; plots; ternary diagrams; tables; bar graphs; histograms
Released2019 09 30
AbstractThe Detour Lake deposit is at a faulted contact between mafic volcanic and siliciclastic to volcaniclastic rocks, differing from other orogenic Au deposits in the dominantly greenschist facies Abitibi region, by possessing amphibolite facies assemblages. Consequently, typical indicator minerals for mineralization, like secondary biotite, may not be useful for locating ore zone, due to the challenge of distinguishing hydrothermal versus metamorphic and magmatic phases. Herein, geochemical and 40Ar/39Ar geochronological data are presented for biotite from mineralized and barren (distal) magmatic rocks to characterize potential geochemical and geochronological variations between biotite types. Petrological observations reveal four biotite types: (1) Biotite hosted in mineralized, sulphidized quartz-calcite veins, (2) halo biotite at the margins of the aforementioned veins; (3) host rock biotite defining the foliation within the mafic volcanic rocks of the deposit; and (4) biotite defining the foliation within the barren meta-plutonic host rocks. Chemical analysis reveals a lower Ti- and higher Mg-content of mineralized biotite types, indicative of secondary hydrothermal processes. 40Ar/39Ar ages for all biotite types (2600-2390 Ma) post-date the main syn-deformation mineralization event at Detour Lake (less than or equal to 2700 Ma). These results suggest chemical variations within biotite are due to a post-mineralization hydrothermal event, thus biotite should be used cautiously as a vector for gold mineralization in amphibolite facies terranes.

Date modified: