| Title | Glacial dispersal of gahnite from the Izok Lake Zn-Cu-Pb-Ag VMS deposit, northern Canada |
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| Author | McClenaghan, M B ;
Paulen, R C; Layton-Matthews, D; Hicken, A K; Averill, S
A |
| Source | Geochemistry: Exploration, Environment, Analysis 2015, 17 pages, https://doi.org/10.1144/geochem2014-317 |
| Image |  |
| Year | 2015 |
| Alt Series | Earth Sciences Sector, Contribution Series 20150140 |
| Publisher | Geological Society of London |
| Document | serial |
| Lang. | English |
| Media | paper; on-line; digital |
| File format | pdf |
| Province | Nunavut |
| NTS | 86H |
| Area | Izok Lake |
| Lat/Long WENS | -115.0000 -108.0000 68.0000 64.0000 |
| Subjects | economic geology; igneous and metamorphic petrology; industrial minerals; metallic minerals; mineralogy; geochemistry; gahnite; sediment dispersal; indicator elements; lead zinc deposits; silver;
copper; sulphide deposits; mineral deposits; drift prospecting; drift geochemistry; till geochemistry; till analyses; bedrock geology; Proterozoic |
| Illustrations | location maps; bedrock maps; tables; geochemical tables; photographs |
| Program | GEM2: Geo-mapping for Energy and Minerals Hudson/Ungava, Northeastern Quebec-Labrador, surficial geology |
| Released | 2015 05 29 |
| Abstract | The Izok Lake Zn-Cu-Pb-Ag volcanogenic massive sulphide (VMS) deposit in the Arctic region of Canada is one of the largest undeveloped Zn-Cu VMS resources in North America. In 2009, the Geological
Survey of Canada initiated a detailed glacial dispersal study of the deposit focused on documenting its associated indicator mineral and till geochemical signatures. Glacial dispersal from the deposit is fan-shaped and was formed by an older SW ice
flow and younger NW ice flow phases. Till samples contain chalcopyrite, sphalerite, galena, and pyrite up to 1.3 km down-ice and gahnite at least 40 km down-ice. Gahnite (ZnAl2O4) is an ideal indicator mineral in till because of its visually
distinctive bluish green colour combined with its high specific gravity (4-4.6) for recovery using density-based separation methods, moderate hardness (physical durability during glacial transport), chemical stability in oxidizing surficial
environments (resistance to post-glacial weathering), and its occurrence in highly metamorphosed VMS deposits such as Izok Lake. Most gahnite grains in till downice are 0.25-0.5 mm in size. Coarser gahnite (0.5-2.0 mm) occurs only in till proximal to
the deposit (<3 km down-ice) and thus is an indicator of proximity to a gahnite-bearing bedrock source. Ore (Cu, Pb, Zn, Ag) and pathfinder element (As, Cd, Bi, Hg, In, Sb, Sb, Tl) contents in the <0.063 mm fraction of till reflect glacial dispersal
up to a maximum of 6 km down-ice. A 15-20 km till indicator mineral sample spacing is sufficient to detect a gahnite glacial dispersal train such as that from the Izok Lake VMS deposit. |
| Summary | (Plain Language Summary, not published)
This journal paper describes the geochemistry of, and indicator minerals in, glacial sediments down ice of the Izok Lake volcanogenic massive sulphide
deposit in Nunavut. This deposit contains zinc, copper , lead and silver. The well known but unmined deposit was used as a test site to develop and test new methods for exploring for base metal deposits in Canada's north and was carried out as part
of the GSC's GEM-1 Project. |
| GEOSCAN ID | 296767 |
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