Synchronic Response of Arctic Ice-Sheets to Global Climate Deterioration During the Plio- Pleistocene
Here, we report the revised chronostratigraphic and new sedimentological data of various ODP boreholes (Legs 151, 162) in the Atlantic-Arctic gateway region to present a coherent glaciation model for the Barents Sea ice sheet over the past 3.5 Ma. Pulses of IRD during the Northern Hemisphere Glaciation (NHG) at ~2.7 Ma indicate consistency of glacial dynamics of circum-Arctic ice sheets to global climate deterioration. However, large-scale expansion of the Barents Sea ice sheet towards the shelf edge are not evident before ~1.5 Ma. This is inferred not only from IRD pulses but also from a step-wise decrease of Siberian river supplied smectite-rich sediments likely caused by ice-sheet blockade and glacigenic wedge growth along the northern and western Barents Sea margin. Large-scale glaciation in the Barents Sea occurs since ~1 Ma (Mid-Pleistocene Transition) and repeatedly advanced to the shelf edge at least 7 times thereafter. The timing is inferred from ice grounding on the Yermak Plateau at ~0.9 Ma attributed to a pronounced ice sheet advance or deep-draft icebergs and higher frequencies of gravity-driven mass movements along the western Barents Sea margin associated with glacial growth.
AGU Fall Meeting Abstracts
- Pub Date:
- December 2007
- 1521 Paleointensity