Lithospheric sulfur cycling during Archean orogenesis

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My research program focuses on our understanding of sulfur cycling through the lithosphere. Sulfur can act as a volatile component of many geological reservoirs on Earth. Consequently, the complex sulfur cycle plays a critical role in a variety of fundamental Earth processes such as regulating the global climate, the living cell, and ore deposit formation. Sulfur is a critical ligand that complexes, transports and concentrates gold in hydrothermal fluids. Similarly, base metals such as nickel, cobalt, copper and zinc, due to their chalcophile nature in sulfur-bearing magmatic and hydrothermal systems, are concentrated in sulfides. Metals are a cornerstone of the Canadian economy and are increasingly important in the development of renewable energies. The global move toward sustainable energies in a low-carbon society has increased the demand for metals (such as nickel and cobalt) to manufacture long lasting batteries. Further, copper remains an important metal in building construction and electronics. While mining is one of Canada's most important sectors and gold being Canada's third most profitable (13 billion$) export, increasingly rare surficial deposits are pushing exploration under cover and to more remote locations. Canada's remote north holds a wealth of these precious and base metals; however, the exploration and mining industries increasingly rely on technologies to predict where metals are localised. My research program focuses on the evolution of tectonic mechanisms that play a role in focusing metals and sulfur in order to better understand how and where metals precipitate and where and on what time-scale sulfur is stored in the Earth's deep lithosphere before being returned to the surface. This knowledge gap is addressed by examining the nature of the mass-independent fractionation of sulfur (MIF-S), which was imparted to sulfur-bearing reservoirs prior to 2.4 billion years ago. This fractionation process led to the unique preservation of this anomalous isotope signature in the Archean sedimentary rock record and has enabled the understanding of the chemical evolution of the atmosphere and hydrosphere. Thanks to recent analytical developments we are now in the privileged position to use MIF-S as an indelible tracer of various lithospheric-scale processes. The research will employ state-of-the-art analytical tools to characterise the temporal evolution of the multiple sulfur isotope composition of metalliferous hydrothermal fluids in the Slave and Superior cratons and magmas in the Ungava Orogen. The outcomes will: 1) enhance the application of MIF-S as a powerful and indelible tracer to understand the source and emplacement pathways of metal-bearing fluids and magmas through the lithosphere, and 2) improve our understanding of the lithospheric-scale transport mechanism of sulfur among different reservoirs, and 3) better align ore deposit research to the targeting critical metals for the global move to renewable energies.