Timing and pattern of the last deglaciation in the Kattegat region, southwest Scandinavia

Abstract

This paper presents evidence on the timing and pattern of the Late Weichselian deglaciation in SW Scandinavia, particularly in the Öresund–Kattegat region before the Allerød interstadial. New radiocarbon ages and evaluated older dates demonstrate that active glacier ice had left eastern Denmark, southern Halland and western Skåne before 14,000 BP. The deglaciation in the Öresund region took place mainly under glacioestuarine conditions in a narrow fjord or inlet with some marine influence, as indicated by radiocarbon‐dated finds of Polar Cod (Boreogadus saida) and the vertebra of a Ringed Seal (Phoca hispida). The Swedish west coast experienced glaciomarine and deltaic ice proximal conditions, where Vendsyssel was at the same time under full marine conditions with little evidence of ice rafting. A paleogeographic interpretation illustrates land, sea and ice configurations around 14,000 BP. We suggest that a subsequent lateglacial transgression reached the entire region almost simultaneously and peaked around 13,300 BP. This led to deposition of an ice‐rafted diamicton (the Öresund diamicton) in Skåne and Sjælland, and of glaciolacustrine mud in Halland. We propose that the complex transgression and regression events recorded in the region were governed by interaction of the eustatic sea level rise, isostatic reponse to glacier unloading and possibly also by damming by an ice stream in the Skagerrak and northern Kattegat.