Late Pleistocene and Holocene geology of the Upper Afon Teifi Valley : parts of 1:10 000 sheets SN54NE, 55SE, 64NW, 65NW, 65NE & 65SW

This report describes the late Pleistocene and Holocene geology of the upper Afon Teifi valley. The morphology of the Teifi and tributary Dulais valleys suggests that the latter represents a preDevensian meander loop of the Tertiary Afon Teifi, with interconnects to the modern Teifi valley seen at Cockshead and Olmarch. The modern Teifi valley south of Olmarch may be glacially-excavated. A number of Devensian valley glacier and Holocene fluvial depositional environments are recognised as landform assemblages. These include glacial till, glaciofluvial gravel deposits (kamiform benches, moraines, outwash plains), glaciolacustrine deposits, and Holocene alluvial deposits.