Eurasian ice‐sheet interaction in northwestern Russia throughout the late Quaternary

Abstract

Sediment successions from the Kanin Peninsula and Chyoshskaya Bay in northwestern Russia contain information on the marginal behaviour of all major ice sheets centred in Scandinavia, the Barents Sea and the Kara Sea during the Eemian ÁWeichselian. Extensive luminescence dating of regional lithostratigraphical units, supported by biostratigraphical evidence, identifies four major ice advances at 100 Á90, 70 Á65, 55 Á45 and 20 Á18 kyr ago interbedded with lacustrine, glaciolacustrine and marine sediments. The widespread occurrence of marine tidal sediments deposited c. 65 Á60 kyr ago allows a stratigraphical division of the Middle Weichselian Barents Sea and Kara Sea ice sheets into two shelf-based glaciations separated by almost complete deglaciation. The first ice dispersal centre was in the Barents Sea and thereafter in the Kara Sea. It is possible to extract both flow patterns from ice marginal landforms inside the southward termination. Accordingly, it is proposed that the Markhida line and its western continuation are asynchronous and originate from two separate glaciations before and after the marine transgression. The marine sedimentation occurred during a eustatic sea-level rise of up to 20 m/1000 yr, i.e. the Mezen Transgression. We speculate that the rapid eustatic sea-level rise triggered a collapse of the Barents Sea Ice Sheet at the MIS (Marine Isotope Stage) 4 to 3 transition. This is motivated by lack of an early marine highstand, the timing of events, and the marginal position of Arkhangelsk relative to open marine conditions.

Ice-free conditions in Novaya Zemlya 35 000-30 000 cal years B.P., as indicated by radiocarbon ages and amino acid racemization evidence from marine molluscs

“…The timing of the deglaciation from mainland Russia is not well constrained, but a number of OSL ages below the youngest till are about 60 Ky (Kjær et al. 2003; Kjær et al. 2006; Henriksen et al.…”

Geophysical constraints on the dynamics and retreat of the Barents Sea ice sheet as a paleobenchmark for models of marine ice sheet deglaciation

“…[]) generally supports the east to west migration over time in major glacier activity [ Siegert et al ., ; Svendsen et al ., ] (e.g., Figure ). However, extensive luminescence dating, supported by biostratigraphical evidence, indicates the separation of the Middle Weichselian Barents Sea and Kara Sea ice sheets into two shelf‐based glaciations (70–65 and 55–45 cal ka B.P., respectively) separated by almost complete deglaciation [ Kjær et al ., ; Larsen et al ., ]. Fluctuating dominance between the Barents and Kara seas at this time is suggested to be a result of oceanographic forcing (cf.…”

“…During the Early Weichselian, an ice sheet, documented as being the most extensive Weichselian ice sheet in Russia [ Svendsen et al ., ], dammed Lake Komi in the Pechora Lowland up to the elevation of the Tsilma Pass in the Timan Ridge (Figure ) [ Mangerud et al ., ]. Whether Lake Komi drained into another lake in the White Sea basin or via an ice‐free corridor between the Scandinavian Ice Sheet and the Kara Sea Ice Sheet is still under debate [ Kjær et al ., ; Larsen et al ., ]. Luminescence dating of beach and shoreface sediments of Lake Komi constrain the age of the maximum lake level to the range 80–100 cal ka B.P., with ice advance thus implied to correlate with MIS 5b [ Mangerud et al ., ].…”

Late Quaternary marine-based Kara Sea ice sheets: a review of terrestrial stratigraphic data highlighting their formation

“…1975). We also now know that the basal thermal regime, bedrock topography and rheologic conditions of the subglacial sediments and bedrock are critical for ice‐sheet expansion and retreat, and that marine‐based ice sheets are instable and prone to massive ice‐discharge events (Heinrich 1988; Broecker & Denton 1989; Siegert & Dowdeswell 1996; Kjær et al. 2006).…”