LATE CENOZOIC HISTORY OF THE SCANDINAVIAN AND BARENTS SEA-ICE SHEETS

The oldest ice rafted material (IRD) on the Voring Plateau is dated to about 11 Ma, and is regarded as evidence that glaciers extended to se a level somewhere around the Nordic Seas at this time. We estimate tha t the major glaciations of Scandinavia and the Barents Sea-Svalbard ar ea started at 2.5-2.8 Ma, when the amount of IRD on the Voring Plateau increased strongly, the deep sea delta(18)O curves indicate the onset of Northern Hemisphere glaciations, and the climate in The Netherland s was so cold that a major glaciation of Scandinavia is inferred. Most of the time until 0.9 Ma, the ice sheets were of intermediate size; t hey probably reached the coastal zone of western Norway for long perio ds. The center of glaciation is inferred to have been further north th an during the later glaciations, and we speculate that this was the pe riod of maximum glacial erosion of the Barents Sea. The largest glacia tions, and also the warmest interglacials occurred during the last 900 kyrs, when the 100 kyr astronomic cycle became important. For the las t glaciation, the Weichselian, the glacial fluctuations are known in g reater detail both for Scandinavia and the Svalbard-Barents Sea region . In Scandinavia the glacial fluctuations apparently followed the 23 k yr precession cycle, whereas in the Barents Sea they followed the 41 k yr tilt cycle. In both areas more than one advance reached beyond the coast. We use the Weichselian record to ''calibrate'' the interpretati on of more indirect evidences of glacial fluctuations, and apply the l atter to the Scandinavian and Barents Sea glacial history since 2.5 Ma .