New results on the evolution of the morphology and vegetation of the Lac d'Annecy Basin (northern French Alps) during the late Pleistocene

The analysis of banquette deposits in the south-west of the Lac d'Annecy pr oved the existence of a palaeo-lac d'Annecy during the last interglacial pe riod up to the earliest Weichselian period. Like the present lake, the pala eo-lac d'Annecy probably has been dammed up by alluvial-cone like deposits of the river Fier. C-14-datation of fossil woods, which have been found in moraines and fluvioglacial fills, has not led to a clear solution of the pr oblem, if the main glacial advance of the Weichselian glacial period took p lace already during the OIS 4 or not until the OIS 2. It was possible to sh ow by pollen analysis that during St. Germain I(OIS 5c) and St. Germain II (OIS 5a) thermophilic woods, during the earliest Weichselian interstadials pine-spruce-woods and during the earliest Weichselian stadials cold steppes with few pine-spruce shares were the dominating vegetation around the lake .