Hydrothermal ore-forming processes in modern and ancient arc-backarc systems

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As Canada's known mineral resources are depleted, there is a growing need for improved geological models of ore-forming systems that will contribute to discoveries at greater depths and in regions with limited historical exploration. The demand for metals (e.g., Cu, Zn, Pb, Au) hosted by hydrothermal (e.g., volcanogenic massive sulphide) and magmatic-hydrothermal (e.g., epithermal, porphyry, intrusion-related gold) ore deposits formed in volcanic arc-backarc systems is becoming especially critical as low-carbon energy sources replace non-renewable resources. Meeting these demands will require an innovative approach to studying volcanic ore systems that integrates an understanding of the controls on mineralization at the district to deposit scale. The proposed research program will test the hypothesis that major ore-forming events throughout Earth's history are the product of significant tectonic changes and that identifying key characteristics associated with these changes will directly contribute to improved exploration models for magmatic-hydrothermal ore deposits. This research will address several fundamental questions: 1) What is the role of the tectonic environment on metal endowment in volcanic ore systems?; 2) What are the factors responsible for significant variations in metal endowment between similar volcanic and tectonic environments?; 3) At what point in the tectonic history of a volcanic terrane do crustal-scale faults develop, and for how long are these faults active?; and 4) How have the major volcanic and tectonic processes controlling ore deposition changed from the Archean to present? In the next five years, this program will focus on the relationship between the development of crustal-scale faults and their use as magma and fluid conduits associated with ore formation in modern and ancient submarine to emergent volcanic settings. This program is subdivided into three main projects to test the hypothesis outlined above. These projects will investigate the metallogeny of the Stikine Terrane in NW British Columbia, characterize the volcanic and structural setting of ore-hosting environments in modern arcs of the SW Pacific, and compare hydrothermal, volcanic, and tectonic processes associated with ore formation in modern and ancient volcanic environments. These projects have a strong HQP focus and will train 13 HQP (3 MSc, 10 BSc) in field mapping, data analysis, and remote-predictive mapping of the seafloor over a 5-year period. The results of this research program will directly contribute to a better understanding of large-scale controls on mineralization within a global tectonic context and to improved exploration models for volcanic ore systems in Canada and globally.