An integrated multiscale approach toward the deformation of Earth's continental lithosphere

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We propose to apply our multiscale numerical modeling to investigate the heterogeneous deformation of Earth's crust and mantle, to develop more rigorous ductile shear zone models, to determine the strength profile and deformation mode of continental crust, and to establish a quantitative method to constrain the tectonic boundary conditions from observations of small scale geological structures. Earth is unique among terrestrial planets in the solar system in that it has plate tectonics causing lithospheric plates to deform in plate boundary and interior regions. Understanding the physics of this deformation is of paramount significance both scientifically, for understanding the evolution of Earth and other planets, and practically for the welfare of human beings who live on the lithosphere, mitigate natural hazards, and derive energy, mineral, and other resources from it. Despite its close relationship to humanity, continental deformation over long terms (millions of years) and across vast space scales (comparable to the size of a continent like the North America) remains poorly understood because of the intrinsically heterogeneous nature of the continental lithosphere. The proposed research is significant not only because of its fundamental scientific implications but also its industrial, and societal applications. Geological structures are signatures of the deformation in Earth's crust and mantle related to the generation of geological hazards like earthquakes, landslides, and slope failures. Geological structures serve as conduits or barriers for fluid and heat fluxes in the crust and mantle that strongly affect the movement of water, gas, oil in the subsurface and the concentration of precious metals and minerals. The findings of the proposed fieldwork will shed light on both the regional tectonics of the study areas as well as on how Earth's continental lithosphere has deformed and evolved in general. The integrated modeling and field approach will lead to more efficient geological mapping, mining, and exploration of mineral and energy resources. The research outcome will thus contribute to Canada's economy in the mining and exploration industry. All this will help to raise Canada's stature as a major international research player. The research program serves as a platform to train and inspire many highly qualified personnel (HQP) in some of the most advanced skills of computing, field mapping, and laboratory instrument operation. Many Western graduate and undergraduate students, visiting scientists, and other research associates will be involved in the research activities. Due to the nature of the proposed research, combining fieldwork, laboratory analysis techniques, and numerical modeling, the HQP will be exposed to a very broad range of research techniques and approaches that will enhance and reach beyond their respective fields of study.