Volcanological, structural, and metamorphic reconstruction of the Snow Lake VMS district

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Volcanogenic massive sulphide (VMS) deposits are copper, zinc and lead deposits that form by the precipitation of metals from black smokers on the sea floor. The deposits form along mid-oceanic ridges, in oceanic volcanic island arcs, and in basins behind the arcs. In ancient rocks, VMS deposits are typically found in volcanic island arc and back arc environments, likely due to the preservation of arc versus mid-oceanic ridge environments. These deposits produce a significant proportion of the world's supply of zinc and are important source of copper and silver as well as rare metals that are used by the "high-tech" industry sector. In Manitoba, VMS deposits are associated with the Snow Lake volcanic island arc and backarc that formed early during the opening of the ancient Manikewan Ocean and were deformed during closure of this ocean due to the movement and collision of tectonic plates. The goal of our project is to reconstruct the tectonic, magmatic, volcanic and metamorphic evolution of the Snow Lake volcanic island arc in order to better understand the metallogenesis of its contained VMS deposits, and to provide new constraints on the evolution and metallogeny of ancient arc volcanic sequences in northern Manitoba and Saskatchewan. The direct beneficiary of the new knowledge generated, and of the highly-qualified geoscientists trained during this research, is the Canadian mining and exploration industry who explore for VMS and related ore deposits in Canada, and globally, and indirectly the many rural, northern Canadian communities that depend on mining as their main economic driver. The minerals and mining sector contributes significantly to the Gross Domestic Product (GDP) of Canada, ($32 billion in 2009) and mining accounts for 19% of Canada's goods exports. Successful exploration is crucial to the sustainability of the Canadian Mining Industry and, therefore, to the well being of all Canadians.