Late proterozoic stratigraphy of northwestern Canada and its record of earth system evolution

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This proposed interdisciplinary research program involves studying the late Proterozoic (c. 1200-540 Ma) geological record of northwestern Canada. The exceptionally preserved stratigraphy in this region records the tectonic evolution of ancestral North America spanning the break-up of the supercontinent Rodinia. Formerly contiguous sedimentary sequences should be found on the margins of the continental fragments that rifted apart from northern and western Canada from about 850 to 550 million years ago. Together, these rocks bear witness to multiple glacial epochs, at least two of which were global in extent, and to the tumultuous transition to a fully oxygenated environment that supported the origin and diversification of animal life. Current understanding of these events suggests that the complex evolution of the Neoproterozoic Earth system reflects interconnections between tectonics, global climate, the biosphere, and ocean chemistry. My research group will combine rigorous fieldwork with state-of-the-art geochemical techniques and innovative coupled climate-geochemical modeling to establish and interpret 1) the timing and nature of northwestern North America's break-up from the supercontinent Rodinia, 2) the influence of rifting and associated magmatism on climate and marine geochemistry, and 3) the tempo of important biogeochemical and biospheric changes and their connection to other events. Fieldwork will center on the Yukon and Northwest territories, where late Proterozoic rocks are superbly exposed in mountainous inliers and belts that have emerged as key localities for addressing these questions of global significance.