The Pleistocene Succession in the Lower parts of the Thames Valley

Abstract

The object of the present communication is to demonstrate the relationships which, in the light of present knowledge, appear to exist between the various Pleistocene and Holocene deposits in the Lower and Middle Thames Valley. For this purpose two cross-sections of the valley have been drawn indicating the relative positions of the deposits which occur at various localities as though they were all present in two localities, one in the Lower, and one in the Middle Thames.As many of the more important deposits in the Lower Thames are represented to the north and south of the river in the Dartford area, we have drawn the one section as if our ideal locality occurred in that neighbourhood. In this section, therefore, the relative altitudes of the various beds above and below present river level are those which are found in that part of the Thames basin. In tributary valleys, or in other parts of the main valley these altitudes are not of course necessarily maintained. In cases where deposits belonging to a particular stage have not been preserved in the Dartford area, but occur in a neighbouring part of the valley, or in a tributary valley, their position in the composite section has been roughly gauged by a process of extrapolation. Similarly when dealing with the Middle Thames, we have drawn our ideal section as though all the deposits occurred in one section of the valley in the neighbourhood of Iver.