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

这个拟议的跨学科研究项目涉及研究加拿大西北部晚元古代（约1200-540 Ma）的地质记录。该地区保存完好的地层记录了跨越罗迪尼亚超大陆分裂的祖先北美的构造演化。在大约8.5到5.5亿年前从加拿大北部和西部分离出来的大陆碎片的边缘，应该发现以前连续的沉积序列。这些岩石共同见证了多个冰河时代，其中至少有两个是全球性的，以及向完全含氧环境的动荡过渡，这种环境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。我的研究小组将把严格的实地考察与最先进的地球化学技术和创新的耦合气候地球化学模型相结合，以建立和解释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，以及3)重要生物地球化学和生物圈变化的速度及其与其他事件的联系。野外工作将集中在育空地区和西北地区，在那里，晚元古代的岩石非常暴露在山区的内部和带中，这些岩石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.