Late Proterozoic stratigraphy of the Yukon and its record of Earth system evolution

育空地区晚元古代地层学及其地球系统演化的记录

• 批准号: 402388-2012
• 负责人: Halverson, GalenPippa
• 金额: $ 3.93万
• 依托单位: McGill University
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2015
• 资助国家: 加拿大
• 起止时间: 2015-01-01 至 2016-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=573268
• 关键词: Late; Proterozoic; stratigraphy; Yukon; its

This proposed interdisciplinary research program involves studying the late Proterozoic (1000-540 Ma) geological record of the Yukon. These rocks are exposed in a series of mountainous inliers extending from the Alaska border to the Mackenzie Mountains in the Northwest Territories. The exceptionally preserved stratigraphy in this region records the tectonic evolution of ancestral North America spanning supercontinental break-up. 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 a tumultuous transition to a fully oxygenated environment that supported the origin and diversification of animal life. The complex evolution of the Neoproterozoic Earth system reflects interconnetions between tectonics, global climate, the biosphere, and ocean chemistry. My research group will combine rigorous fieldwork in the Yukon with state-of-the-art geochemical techniques and innovative coupled climate-biogeochemical modeling to establish and interpret the 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 connections to other global events. The research will involve a team of three current McGill PhD students, undergraduate students, and a network of international collaborators. The outcomes will directly assist exploration for sediment-hosted Cu and Fe in northwestern Canada and possible links to mineralized belts on formerly contiguous continents.

这个拟议的跨学科研究项目包括研究育空地区晚元古代（1000-540 Ma）的地质记录。这些岩石暴露在从阿拉斯加边界延伸到西北地区麦肯齐山脉的一系列山地内部。该地区异常保存的地层记录了北美祖先跨越超大陆分裂的构造演化过程。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期，其中至少有两个冰期是全球性的，也见证了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。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。我的研究小组将在育空地区进行严格的实地考察，结合最先进的地球化学技术和创新的耦合气候-生物地球化学模型，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)裂谷作用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全球事件的联系。这项研究将涉及一个由三名麦吉尔大学在读博士生、本科生和一个国际合作者网络组成的团队。研究结果将直接帮助加拿大西北部沉积物中铜和铁的勘探，并可能与以前相邻大陆上的矿化带联系起来。