Understanding processes and events that formed the Canadian Polar Margin

了解形成加拿大极地边缘的过程和事件

• 批准号: 387983493
• 负责人: Professorin Dr. Cornelia Spiegel
• 金额: --
• 依托单位: Fachgebiet Geodynamik der Polargebiete
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2017
• 资助国家: 德国
• 起止时间: 2016-12-31 至 2020-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/387983493?language=en
• 关键词: Understanding; processes; events; formed; Canadian

The northernmost margin of the North American continent is constituted by the Pearya terrane of Ellesmere Island. This remote area is difficult to access and the development of this margin segment is poorly known. Recent Arctic expeditions of the BGR provided the opportunity to study structural and geomorphological properties of Pearya and adjacent Arctic areas, and to collect a dense set of thermochronological samples. Thermal history models obtained from initial apatite fission track and (U-Th-Sm)/He (AFT & AHe) data suggest that Pearya experienced km-scale erosion since the Eocene, and that the area may share a similar erosion history with even less accessable areas of the Central Arctic and the Siberian Shelf. Studying Pearya will therefore give insights into dynamic processes and events that may have dominated the poorly constrained Cenozoic tectonic history of the Arctic. For this study we aim to apply different thermochronological dating methods to rocks from Pearya. From the data, we expect three main results: 1) better understanding timing and extent of the Cenozoic Eurekan deformation and its relation to other areas of the Arctic; 2) understanding the influence of crustal inheritance on intraplate orogeny, using the example of the Eurekan intraplate orogen across Ellesmere Island; 3) better constraining the efficiency of glacial erosion in tectonically inactive landscapes, as well as the role of lithology contrasts for erosion efficiency. Thus, our study will provide new insights into the Cenozoic plate tectonic evolution of the Arctic realm as well as on general processes governing the erosion of mountain belts.

北美大陆的最北端由埃尔斯米尔岛的皮亚地体构成。这一偏远地区很难进入，这一边际区段的发展情况鲜为人知。最近对BGR进行的北极考察为研究皮尔亚和邻近北极地区的结构和地貌特性以及收集密集的热年代学样品提供了机会。根据初始磷灰石裂变径迹和(U-Th-Sm)/He(AFT&AHE)数据获得的热历史模型表明，自始新世以来，皮亚经历了千米级的侵蚀，该地区可能与北极中部和西伯利亚陆架更难接近的地区有着相似的侵蚀历史。因此，对皮亚的研究将使我们深入了解可能主导了北极缺乏约束的新生代构造史的动态过程和事件。在这项研究中，我们的目标是将不同的热年代学方法应用于皮尔雅的岩石。从这些数据中，我们预计有三个主要结果：1)更好地了解新生代尤里坎变形的时间和程度及其与北极其他地区的关系；2)以横跨埃尔斯米尔岛的尤里坎板内造山带为例，了解地壳继承对板内造山作用的影响；3)更好地限制构造不活跃地貌中冰川侵蚀的效率，以及岩性对比在侵蚀效率方面的作用。因此，我们的研究将为研究北极地区新生代板块构造演化以及控制山脉带侵蚀的一般过程提供新的见解。