Nivation and Local Glaciation in N. and S. Sweden. A Progress Report

Abstract

An ongoing geomorphological research project on nivation and local glaciation is testing the following working hypothesis.

After the main Weichselian deglaciation in south Sweden, periods of cold tundra conditions returned, e.g. in the Younger Dryas period. Fossil ice-wedge casts and rocks with wind-polished facets and flute marks indicate permafrost climate and strong winds with snow-drifting from easterly and westerly directions. Large masses of drifting snow were trapped in the canyon valleys of Söderäsen and other horst ridges, where nivation hollows and small glacial cirques were slightly rejuvenated. Niveo-eolian sand was deposited in some hollows and also incorporated in some moraine-like deposits. The bedrock hollows and cirques were mainly excavated during the much longer tundra periods before the advances of the Quaternary main ice sheets over Scania. But the hollows survived the erosional impact of the ice sheets.

The work to test the hypothesis is making progress, by analysis of the Late-Glacial forms and material in south Sweden, by comparisons with landforms, material and processes in the actual mountain tundra of Abisko in the north, and by comparisons with similar work by scientists in western Norway, northwest England/Scotland and Middle Europe. The studies will also be of general interest in arctic and alpine geomorphology, as they throw light on the genesis of critical types of debris deposits such as small cirque moraine ridges, protalus ramparts, rock-glacier lobes, gelifluction and debris-flow deposits.