Valley sediments as evidence of Prehistoric land-use : a study based on dry valleys in South East England
Several recent studies have drawn attention to the existence of substantial alluvial and colluvial valley fills which accumulated over archaeological time. These fills have been variously associated with climatic change and anthropogenic effects. In the case of colluvial deposits on the English chalk their extent, nature and cause was far from clear. It was hoped that a detailed investigation of the relationship between colluvial valley deposits and prehistoric land-use on the South Downs would contribute to the identification of causative factors and establish a methodology which might be applied to the investigation of deposits elsewhere. Three areas, all of them well known archaeologically, were investigated in detail: Kiln Combe, near Eastbourne; Itford Bottom, near Lewes; and Chalton, near Petersfield. In each a trench was dug across the valley floor and detailed drawings of the sediments made. A strip was then hand excavated and all the artifacts were three dimensionally recorded in order to date the deposits. The environmental conditions under which they had accumulated were studied by mollusc and sediment analysis. Work in the study areas showed that colluvial deposits were fairly widespread, contained large quantities of artifacts and accumulated over a long period, largely as a result of land-use factors. The existence of so much eroded sediment, containing an important component of Pleistocene loess, seems to suggest that some pedological changes have occurred during the Postglacial. The possible effects of these on land-use regimes and settlement patterns on the chalk are considered.