Understanding processes and events that formed the Canadian Polar Margin

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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.