Dynamics of ductile crust

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Our ability find mineral resources is guided by our understanding of past geologic processes that created those mineral resources, which can suggest the geologic signatures that can guide us to future resources. The precambian shield forms a very large part of Canada, and hosts many of the country's mines as well as undiscovered future resources. Despite this reliance on some of the oldest rocks on Earth for our mineral wealth, we still do not fully understand the large scale geologic processes that formed them. Two major enigmas stand between us and understanding these early rocks (and modern ones). The first enigma is how subduction initiates, at a tectonic plate edge. Subduction is the process by which one edge of a plate sinks into the Earth's mantle below the crust of an adjacent plate, pulling its own plate behind itself across the surface of the planet. Using sophisticated computer simulation of the physics (stresses, strains, heat flows, and heat-generated softening of rocks), I will investigate whether the ductile deformation of the softer water-altered (serpentinized) rocks of the ocean floor, buried under sediments at a continental margin, can destroy the mechanical integrity of a tectonic plate there, permitting the severed edge to sink, initiating subduction.