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: 408457-2012
• 负责人: Halverson, GalenPippa
• 金额: $ 1.46万
• 依托单位: McGill University
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Northern Research Supplement
• 财政年份: 2016
• 资助国家: 加拿大
• 起止时间: 2016-01-01 至 2017-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=596157
• 关键词: Late; proterozoic; stratigraphy; Yukon; its

This proposal links with a concurrent Discovery proposal to pursue an interdisciplinary research program on the late Proterozoic (c. 1000-540 Ma) geological record of the Yukon. These rocks are exposed in a series of mountainous inliers extending through the north-central Yukon, from the Alaska border in the west to the border with the Northwest Territories in the east. The exceptionally preserved strata in this region record the tectonic evolution of ancestral North America spanning the break-up of the supercontinent Rodinia. Formerly contiguous sedimentary sequences occur 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 McGill undergraduate and 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 adjacent continents.

这一建议与一个并行的发现建议联系起来，以进行关于晚元古代（c. 1000-540 Ma）的育空地区地质记录。这些岩石暴露在一系列山区内层中，这些内层延伸穿过育空地区中北部，从西部的阿拉斯加边界到东部与西北地区的边界。该地区保存完好的地层记录了北美大陆的构造演化，跨越了Rodinia超大陆的分裂。大约8.5亿年至5.5亿年前，加拿大北方和西部断裂的大陆碎片边缘出现了以前连续的沉积序列。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，以及一个动荡的过渡到一个充分氧化的环境，支持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。我的研究小组将把联合收割机在育空地区的严格实地考察与最先进的地球化学技术和创新的气候-地球化学耦合模型相结合，以建立和解释1）北美西北部从超大陆Rodinia分裂的时间和性质，2）裂谷和相关岩浆活动对气候和海洋地球化学的影响，（3）重要地球化学和生物圈变化的克里思及其与其他全球事件的联系。该研究将涉及麦吉尔大学本科生和本科生团队以及国际合作者网络。这些成果将直接有助于勘探加拿大西北部沉积物中的铜和铁，以及与以前相邻大陆上矿化带的可能联系。