A Holocene Alluvial Sequence in the lower Tyne Valley, Northern Britain: A Record of River Response to Environmental Change

Abstract

Palaeoenvironmental investigations have been made of late Quaternary sediments infilling the lower Tyne valley at Scotswood, Newcastle-upon-Tyne, 18 km upstream from the mouth of the river. Attention has focused on the Holocene alluvial sedimentary sequence using sedimentological, geochemical and palynological analyses. Holocene valley floor development from c. 7500 BP has been largely dominated by a tendency towards river aggradation with some limited lateral and vertical reworking of sediments. Four alluvial fills have been identified and dated to: 1) c. 7500-4800 BP; 2) from c. 2590 BP up to the early first millennium AD and possibly as late as medieval times; 3) between the medieval period and the early seventeenth century, and 4) between the seventeenth and nineteenth centuries. Episodes of incision are dated to c. 4800-2590 BP, and to the period following the early seventeenth century. Marked variations in the rates and nature of sedimentation and erosion appear to coincide with rising post-glacial sea levels and, during the later Holocene, periods of significant catchment land use change and/or climatic deterioration.