GEOSCAN Search Results: Fastlink


TitleAn orientation study of the heavy mineral signature of the NICO Co-Au-Bi deposit, Great Bear magmatic zone, NW Territories, Canada
AuthorMcMartin, I; Corriveau, L; Beaudoin, G
SourceGeochemistry: Exploration, Environment, Analysis vol. 11, 2011 p. 293-307,
Alt SeriesEarth Sciences Sector, Contribution Series 20090365
PublisherGeological Society of London
Mediapaper; on-line; digital
File formatpdf
ProvinceNorthwest Territories
NTS85N; 86C; 86D; 86E; 86F; 86K; 86L
AreaGreat Bear Lake; Lac la Martre; Hottah Lake
Lat/Long WENS-119.0000 -116.0000 67.0000 63.0000
Subjectsgeochemistry; economic geology; mineral occurrences; cobalt; gold; bismuth; copper; heavy minerals; heavy mineral analyses; heavy minerals geochemistry; magnetite; Great Bear magmatic zone; NICO deposit; Sue-Dianne deposit
Illustrationslocation maps; tables; photomicrographs; plots
ProgramGEM: Geo-mapping for Energy and Minerals, Iron-oxide Copper-gold (IOCG) / Multiple Metals - Great Bear Lake (NWT)
Released2011 12 07
AbstractAn orientation study around the NICO Co-Au-Bi deposit in the Great Bear magmatic zone of NW Territories, Canada, was initiated in 2007 to establish a practical guide to geochemical and mineralogical exploration for iron oxide coppergold deposits in glaciated terrain. Bedrock and till samples were collected up-ice, proximal and down-ice from mineralization and host rocks, to characterize their indicator mineral signatures. Results demonstrate that gold grain abundance, size and shape, as well as magnetite and hematite composition, have the best potential to fingerprint the mineralization at NICO. Pristine-shaped gold grains indicative of a local bedrock source and a short distance of glacial transport are relatively abundant in till samples collected immediately down-ice from several mineral occurrences at NICO and none were recovered up-ice. Iron oxide composition using preliminary discriminant diagrams shows some potential, using Ni/(Mn+Cr) versus Ti+V plots. In particular, magnetite and hematite from till samples collected over, or directly down-ice of, the NICO deposit have lower Ti+V compositions compared to magnetite and hematite from till collected up-ice from mineralization. Potential non-ferromagnetic indicator minerals are either not chemically stable in surface sediments (arsenopyrite, chalcopyrite, pyrite), not sufficiently coarse-grained or resistant to glacial transport (bismuthinite, tourmaline, ferroactinolite), not abundant enough in the mineralized bedrock (scheelite, molybdenite, cobaltite, allanite), or not sufficiently heavy (tourmaline) to be useful at NICO but may be at other deposits in the region or elsewhere in glaciated terrain. The development of indicator mineral methods, together with till geochemistry, will be tested with further sampling over the Great Bear magmatic zone.