A rare record of late Neogene glaciation from the north east Greenland margin | CU Experts

<p>Studies based on deep ocean drilling cores points to North-East Greenland as a focal point for ice sheet accumulation incurring much earlier than the Pleistocene Northern Hemisphere glaciation. The build-up of marine-based ice sheets in these parts is critical to the cooling of the Nordic Seas and the Arctic Ocean, considered as a pre-condition for the modern ocean &#8220;conveyor belt&#8221; circulation. However, proximal sedimentary records that can shed light on the timing and climate background of early Greenland Ice Sheet evolution are lacking. In 2008 a series of shallow cores were drilled by the Kanumas consortium on the NorthEast Greenland shelf and Cenozoic sediments were recovered at several sites. Here we present litho- and palynostratigraphic information, along with new cosmogenic isotope results, of a 110 m long sediment core (Kanumas 13). The core study, supported by regional seismic data, suggests that ice streams may have been active on the North-East Greenland margin since middle-late Miocene. Geochemistry and magnetic susceptibility data indicate that an abrupt change in sediment source occurred at 50.8 m. The shift in provenance is accompanied by a transition to more open marine conditions. The implications for the Greenland Ice Sheet and Artic climate development will be addressed in the presentation.</p>

Knutz P; Nielsen T; Sliwinska K; Fyhn M; Hopper J; Jennings A; Bierman P; Christ A; Corbett L; Hidy A

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