Characteristics of the MIS 5 pollen record from Lathuile Gare, 456 m a.s.l., at the SW border of the Lac d’Annecy (northern French Alps)

Abstract

The layers studied, parts of banquettes, consist of limnic clayey-silty fine sediments with some intercalated horizons of shaly coal and lacustrine mud flow rubble. In the lower part of the record the Bornette interglacial has been established. This is characterised by high values of Corylus and a significant presence of Quercus and Hedera in addition to a wide-spread presence of Buxus,Ulmus and Carpinus. A linkage of this interglacial to the Eemian (MIS 5e) can be considered an applicable hypothesis. Quantitatively, however, Alnus and Picea exceed all these thermophytics. However the lower part of Lathuile Gare is also characterised by palynological duplications untypical of the Eemian, for example two distinct peaks of Corylus linked to a significant decline in Picea in PZ 3 and 5 and higher values of Abies and Picea in PZ 4 and 6. Possibly these duplications can be explained by a rapid sub-aquatic flow causing a doubling of the beds. In the upper part of the Lathuile Gare record two mean climatic recession periods in the lowest and the second uppermost section (PZ 9 and 15) were detected with increased values of NAP and Pinus in PZ 9 and decreased proportions of Picea in PZ 15. They represent the Chaperon b interstadial and the Lathuile stadial correlated hypothetically with the St. Germain Ib (MIS 5c2) and the Melisey II (MIS 5b) stadial. The enclosed middle part, the Chaparon c interstadial, revealing similarities with the St. Germain Ic (MIS 5c1), is dominated by Picea and Pinus. Only a few thermophilous taxa occur in the middle of this interstadial in PZ 11.