NEW CONSTRAINTS ON THE LIMITS OF THE BARENTS-KARA ICE SHEET DURING THE LAST GLACIAL MAXIMUM BASED ON BOREHOLE STRATIGRAPHY FROM THE PECHORA SEA

Abstract

A new, 14C-verified borehole stratigraphy provides the first age-controlled reconstruction of the late Quaternary glacial history of the Pechora Sea (southeasternmost Barents Sea). A complete glaciation of the Pechora Sea is confirmed for middle Weichselian time, prior to ca. 35–40 ka. Composition of glacial erratics indicates that ice was moving from or across southernmost Novaya Zemlya and Vaygach Island. After a brief interstadial period with normal marine conditions, the Pechora Sea was affected by a drop in sea level and a drier climate. Sub- sequently, the late Weichselian Barents-Kara ice sheet occupied the northwestern part of the Pechora Sea, but did not reach the coast of the Pechora lowland, as previously believed. These data provide a new constraint on the Last Glacial Maximum (LGM) ice-sheet limits in the Eurasian Arctic. The inferred direction of the Last Glacial Maximum ice movement in the Pechora Sea was from the northeast, but with a stronger northern component than the penultimate glacia- tion. The ice sheet retreated early, ca. 13 ka, after which the shallow Pechora Sea was subjected to strong erosion during the postglacial sea-level rise.