VARIABLE LATE PLEISTOCENE ICE SHEET AND ICE CAP EXTENT IN THE EURASIAN NORTH

Field research over the past decade constrains the largest LGM ice sheet load to the northern and western Barents Sea with projected margins in the southern Barents Sea and central Kara Sea. Though marginal areas, like Vaigach Island appear to have been covered by the thinning ice sheet edge. The LGM ice sheet in northern Eurasia was relatively diminutive equivalent to ~ 7 m of global sea level. Maximum extent of this ice sheet was short lived from c. 22 ka to 14 ka and with full deglaciation prior to 10.5 ka. Other ice geometries existed during the LGM with a separate ice cap in the Kara Sea area, potentially on Svernaya Zemlya that terminated on Tamyr Peninsula. Older glaciations (c. ~ 60 ka) were particularly more extensive in the Kara Sea with evidence of large-scale glaciotectonism on Yamal and Yugorsky Peninsulas. On Yamal, a single glaciation c. 60 ka ago is indicated by the Kara diamicton, that reflects regional glaciation with glacier deformation from the south to southwest. The cliffs of Cape Shpindler on Yugorski Peninsula reveal two glacier advances and three ice-free periods. Interglacial conditions are inferred from a sequence of marine to fluvial sediments. During the older glacial event (pre-Holstenian, MOI 8), ice moved southwards from an ice-divide over Novaya Zemlya and overrode and disturbed interglacial sediments. After a period of fluvial deposition under interstadial or interglacial conditions, the area was again subjected to glacial overriding, with ice moving northwards, from an ice divide on mainland Siberia. This younger glacial event is correlated to the one glacier advance on Yamal Peninsula; both show ice deformations from S to N. The stratigraphic records bordering the Kara Sea show greater complexities in glacial dynamics and geometries than depicted by concentric ice sheet models centered on the Eurasian shelf seas for the LGM and older glaciations.