The evolution of the River Medway, SE England, in the context of Quaternary palaeoclimate and the Palaeolithic occupation of NW Europe

The Medway is a river of considerable antiquity that has had an important role within the evolution of drainage in southeast England. Its upper catchment has expanded during the latter part of the Quaternary as a result of river capture. However, it has a much shorter course as an independent river than it did half a million years ago, since its lower course was truncated when the Anglian glaciation caused the Thames to be diverted into the lower Medway valley, across what is now eastern Essex. Correlation of gravel terraces in the present Lower Medway with those of the Lower Thames is readily achieved by long-profile projection to and from the Southend area, where terraces of the now-drowned post-diversion Thames-Medway valley are preserved. Correlation between the Lower and Upper Medway is more problematical, but a revised scheme can be suggested, one that requires most of the surviving deposits in the upper valley to be of relatively recent age. The suggested correlations take account of faunal and archaeological components of the deposits, as well as projected downstream gradients and the height above the river of terrace remnants, the latter newly established as an important measure of fluvial incision in response to progressive uplift and, therefore, as a potential means of age estimation.