Stratigraphic and morphologic constraints on the weichselian glacial history of northern prins karls forland, western svalbard

Uncertainty remains if ice–free marginal areas existed on the west coast of Svalbard during the Late Weichselian. Field mapping and correlation to well dated raised beach sequences on nearby Brøggerhalvøya reveal the existence of two generations of raised beach deposits on northern Prins Karls Forland. Distinct beach ridges rise up to the inferred Late Weichselian marine limit at 18 m a.s.l. Discontinuous pre–Late Weichselian beach deposits rise from the Late Weichselian marine limit up to approximately 60 m a.s.l. Expansion of local glaciers during the Late Weichselian is indicated by the limited distribution of a till that overlies parts of the older beach sequence. Stratigraphic data and chronological control indicate deposition in a shallow marine environment before 50 ka bp. Correlation to stratigraphic sites on western Svalbard suggests deposition at c. 70 ±10 ka. Glaciotectonic structures disclose expansion of local glaciers into the For–landsundet basin during stage 4 or late stage 5 high relative sea level. Palaeotemperature estimates derived from amino acid ratios indicate that during the time interval c. 70 to 10 ka the area was exposed to cold subaerial temperatures with low rates of racemization. Pedogenesis and frost–shattered clasts at the contact between c. 70 ka deposits and Holocene deposits further indicate a prolonged period of subaerial polar desert conditions during this time interval. The evidence suggests that the Barents Sea ice sheet did not extend across northern Prins Karls Forland during the Weichselian. It is inferred that during the Late Weichselian, ice was drained throughout the major fjords on the west coast of Svalbard and that relatively large marginal areas experienced polar desert conditions and minor expansions of local glaciers.