Interglacial and glacial climate oscillations in a marine shelf sequence from northern Denmark - A multidisciplinary study

A 22.5 m long marine shelf sequence in northern Denmark covers the climatic shifts from glacial environments, through interglacial and into early glacial conditions. The interglacial was interrupted by two cool intervals. Also the early glacial succession experienced oscillations of the climate, and a period with ameliorated temperature conditions has been separated as an interstadial. These results are based on a multidisciplinary high-resolution study of lithology, foraminifera, ostracods, macrofauna, diatoms and stable isotopes in a silty clay sequence from a borehole at Norre Lyngby (70.5-48.0 m depth). The lithostratigraphy and the variations in depositional environment in the area is supported by a reflection seismic profile across the core site. The chronostratigraphy is discussed on the basis of biostratigraphical correlation and seismostratigraphy as well as Optically Stimulated Luminescence (OSL) dating and amino acid measurements. The biostratigraphy and the OSL dates suggest an Eemian age for the interglacial, while amino acid results point to an older age. If the interglacial is confirmed as Eemian, we believe that the succeeding interstadial period is likely to be correlated with the Brorup Interstadial. The climatic changes in this eastern part of the North Sea region are closely linked with changes in the North Atlantic circulation pattern, and the environmental fluctuations at Norre Lyngby are therefore believed to reflect fluctuations in the past regional climatic and oceanic system. (C) 1998 Published by Elsevier Science Ltd. All rights reserved.