Diatom stratigraphy related to Late Weichselian sea-level changes in Sunnmøre, Western Norway.

Abstract

In sediment cores from four small basins from 44 to 26 m above sea-level, the boundaries between marine, brackish and lacustrine sediments are precisely identified through their distinct diatom stratigraphy. In all basins the diatom successions demonstrate a development from marine to lacustrine environments. The basins, today being lakes or bogs, were isolated from the sea between 12.400 to 9.200 radiocarbon years B.P., at the end of the Late Weichselian. The emergence was fast during the Bøllingen and Allerød (12.000-11.000 yr BP), and slower during the Younger Dryas (11.000-10.000 yr BP). The slow emergence was probably a main reason for the formation of the morphological distinct Tounger Dryas shore-line.