SOILS OF THE CENTRAL NORTH-DOWNS - THEIR DISTRIBUTION, DERIVATION ANDGEOMORPHOLOGICAL SIGNIFICANCE

This investigation reports the results of a systematic soil survey acr oss the central North Downs backslope. Sediment origin is determined b y textural and heavy mineral analysis of 114 soil samples and comparis ons with likely parent materials. Soil distribution and soil-sediment relationships revealed are more complex than the WOOLDRIDGE & LINTON ( 1955) and later models of landscape evolution suggest. The study shows a constant threefold stratigraphical zoning in the Chalk mantle viz: Clay-with-flints sensu stricto, Plateau Drift and loess, except over m uch of the marked bench between 137-198 m, where Clay-with-flints sens u stricto is absent. This suggests a different geomorphological histor y for this part of the backslope. Difficulties with the acceptance of the origin of Clay-with-flints,sensu stricto as an illuvial product of Quaternary weathering on an in situ Palaeogene cover are discussed.