The Kesgrave Sands and Gravels: ‘pre-glacial’ Quaternary deposits of the River Thames in East Anglia and the Thames valley

Abstract

This paper reviews the Kesgrave Sands and Gravels as evidence for the pre-glacial history of the River Thames and its main tributaries. Attention is given to the definitions of the deposit, the lithological and sedimentological properties, and the geographical and stratigraphical variations of these properties. Also described are the terrace landforms formed by the Kesgrave Sands and Gravels and the Iithostratigraphical and geomorphological basis by which individual terraces are correlated across the region. The relationship of the Kesgrave Sands and Gravels to the palaeosols developed on their surfaces, to contemporaneous coastal sedimentation and to neotectonic uplift in the headwater regions and subsidence around the North Sea margins is outlined, along with possible evidence for glaciation in the headwater regions. The paper concludes with a review of the palaeoclimatic and stratigraphical evidence which indicates that most of the unit was deposited by periglacial river activity during the late Early Pleistocene and the early Middle Pleistocene between about 1.81 and 0.46 Ma bp A possible scenario explaining the factors forcing river activity in this part of the Quaternary is proposed. The paper also outlines the role of Richard Hey in the identification and interpretation of this sediment body.