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: 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=573412
• 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.

这项建议与同时发现计划相联系，以开展一项关于育空地区晚元古代(约1000-540 Ma)地质记录的跨学科研究计划。这些岩石暴露在一系列穿过育空地区中北部的山区内，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。以前连续的沉积层序出现在大约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。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，并见证了向支持动物生命起源和多样化的完全充氧环境的动荡过渡。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气候-生物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)裂谷和相关岩浆活动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全球事件的联系。这项研究将包括一个由麦吉尔本科生和本科生组成的团队，以及一个国际合作者网络。这些成果将直接有助于在加拿大西北部寻找以沉积物为宿主的铜和铁，并可能与以前相邻大陆上的矿化带建立联系。