Last interglacial and devensian deposits of the River Great Ouse at Woolpack Farm, Fenstanton, Cambridgeshire, UK

This paper describes Pleistocene fluvial deposits of the River Great Ouse a t Woolpack Farm, Fenstanton, Cambridgeshire, UK. These sediments consist of a basal gravel, fossiliferous fluviatile muds. sands and gravels later dis turbed and formed into a diamicton, and overlying gravels. The regional cli mate inferred from palaeobotany, Mollusca, Coleoptera and vertebrates from the diamicton indicates temperate conditions. Coleopteran evidence suggests a mean July temperature of ca. 21 degrees C, 4 degrees C warmer than today in eastern England, and winter temperatures a little colder than at presen t. Molluscan assemblages indicate a slight brackish influence during deposi tion of the muds which form the diamicton. The gravel succession is represe nted by three members which have a broad distribution in the Great Ouse Val ley, and which were laid down in a braided river under periglacial conditio ns. The occurrence of permafrost is indicated by the presence of ice wedge casts in the gravels. The pollen and macrofossil evidence from the diamicto n suggests correlation with Ipswichian substage IpII (Pinus-Quercetum mixtu m -Corylus phase). The basal gravel is of pre-Ipswichian age. A Devensian a ge is proposed for the overlying gravels and their attendant periglacial ph enomena. (C) 2000 Elsevier Science Ltd. All rights reserved.