Imaging and characterization of rifted continental margin structures using geophysical methods: seeking deeper constraints and their tectonic implications

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Canada's submarine limits on the East Coast and in the Arctic are characterized by rifted continental margins, the products of the opening of modern oceans. Despite their territorial and economic importance due to hosting significant energy reserves, these margins remain largely underexplored and the processes that created them are not fully understood. Rifted continental margins are generally classified as magma-rich/volcanic margins or magma-poor/non-volcanic margins. Canada's East Coast hosts both types of margins as well as the transitions between them, providing a natural laboratory for studying rifting processes and how they vary along a rifted continental margin. Great insight can also be obtained by stitching the oceans back together to study how well the conjugate margins match, how asymmetries develop, and whether those asymmetries existed long before the oceans opened. These rifting processes have a profound impact on subsequent sediment deposition and basin evolution, such that developing a better understanding of the crustal variability beneath them can reduce exploration risk and cost. My research program involves studying rifted continental margins and their conjugates in order to contribute to global knowledge on how these margins develop while providing insights on how these rifting processes impact petroleum systems. The short-term goals are to better constrain our current crustal models of rifted continental and transitional crust by taking advantage of new geophysical datasets being acquired on the eastern Canadian margin, as well as on the conjugate margins. These efforts will involve (1) seismic processing work to provide improved images of the crustal variations both along and across conjugate pairs; (2) detailed seismic interpretation work to relate geological boundaries with their geophysical character both within and across conjugate pairs; and (3) gravity inversion work to extend newfound seismic constraints to greater depth and over a broader region. The longer-term goals are to continue to undertake original scientific crustal-scale seismic experiments, in conjunction with industry, government, and international collaborators, over key regions where data gaps remain and where the current state of knowledge does not adequately explain the observations.The proposed research is important to the energy exploration industry and all levels of government due to the territorial and economic impact of enhanced exploration. The gravity inversion methods developed will be of particular strategic importance to Canada as they will provide a low-cost approach to characterizing the deep structure of the Arctic where the federal government has identified responsible development as a research priority. Lastly, 10 highly qualified geoscientists will be trained for work in academia, government, and industry in Canada and internationally.