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

这项拟议的跨学科研究计划包括研究加拿大西北部的晚元古代(约1200-540 Ma)地质记录。该地区保存完好的地层学记录了祖先北美在罗迪尼亚超大陆解体期间的构造演化。以前连续的沉积序列应该在大约8.5亿到5.5亿年前从加拿大北部和西部裂开的大陆碎片的边缘找到。这些岩石共同见证了多个冰川时代，其中至少有两个是全球性的，并见证了向完全充氧环境的动荡过渡，支持了动物生命的起源和多样化。目前对这些事件的理解表明，新元古代地球系统的复杂演化反映了构造、全球气候、生物圈和海洋化学之间的相互联系。我的研究小组将结合严格的野外工作、最先进的地球化学技术和创新的气候-地球化学耦合模型来建立和解释1)北美西北部从罗迪尼亚超大陆分裂的时间和性质，2)裂谷和相关岩浆作用对气候和海洋地球化学的影响，3)重要的生物地球化学和生物圈变化的节奏及其与其他事件的联系。田野调查工作将集中在育空和西北地区，那里的晚元古代岩石出露在山区内部和带中，这些地区已经成为解决这些具有全球意义的问题的关键地点。

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.