Spatial distribution and genetic models of Cu-Ni-PGE systems associated with the Sudbury structure

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Sudbury is a unique place on Earth. The Sudbury basin is a deformed meteoritic impact crater (now filled with sedimentary rocks) that was created 1,850 million years ago. The impact of the meteor produced a crater estimated at 200 km diameter and the energy released on impact melted a large volume of rocks. Cooling of these rocks resulted in igneous rocks grouped as the Sudbury Igneous Complex (SIC). Associated with these rocks and with the impact structure are large reserves of (Cu), nickel (Ni), gold (Au) and metals of the platinum group elements (PGE), such as platinum (Pt) and palladium (Pd). These metals were mobilized by sulfur-rich liquids (sulfide melts) formed at high temperatures and also by hot aqueous fluids (hydrothermal fluids) circulating around the superheated impact crater. However, the distribution of economic concentration of metals (for the extraction and industrial development) is complicated because this ancient impact site has been affected by deformation, metamorphism and circulation of hydrothermal fluids in several occasions after the crater was formed and the SIC was completely cooled. Our interest, in particular, is focused on the distribution of Cu-Ni-PGE mineralization, commonly known as "footwall" deposits, which have complex distribution and geometries and are difficult to locate around the Sudbury Structure. The objective of this project is to determine how the combination of magmatic, metamorphic, and hydrothermal processes control the current distribution of Cu-Ni-PGE ores. The goal is to develop methods, based on detailed mapping and analysis of existing rocks, that can be used as exploration vectors to find Cu-Ni-PGE resources. The Canadian economy is partly resource based and the mining sector contributes significantly to the Gross Domestic Product (GDP) of Canada. In addition, extraction of metals is an essential part of industrialization and development worldwide. Because mining is prone to cyclical fluctuations in metals prices, diversification of metals that can be extracted from one mining district provides a stronger economic foundation and minimizes the impact of metal price volatility.