Development of a regional model for the Devensian Glaciation of County Durham for use in the assessment of sand and gravel resources

Abstract The sand and gravel resources of County Durham are mainly of Quaternary age, predominantly dating from the latter part of the Devensian stage of the Pleistocene and are the result of a complex pattern of glacial recession. A recent study predicted the distribution of drift deposits from a model based on published information, limited field observations and the analysis of approximately 6000 items of subsurface information; predominantly borehole records. This model, which describes the sequence of events during the Devensian glaciation of the area and infers palaeogeographical changes was an essential element in the assessment of the nature and distribution of granular Sediments and the prediction of mineral quality. The assessment identified 178 km 2 of potential resource, in both outcrop and subcrop, 53 km 2 of which had not been previously shown on published maps and plans.