POST-GLACIAL EROSION OF THE NORTH YORKSHIRE COAST FROM THE TEES ESTUARY TO RAVENSCAR

Abstract

Summary This length of coast has been examined for physical evidence of the changes which have occurred in the past 10,000 years. The present rate of cliff foot recession has been determined by survey to average thirty feet per century for the bare shale foreshore and cliffs. The presence of cliff foot debris on the solid coast and glacial drift in the bays results in an average of about sixteen feet per century for cliff foot recession of the whole length of coast, and as active erosion has only reached the cliff top in certain stretches, the average erosion of the cliff top is about seven feet per century. Knowledge of post-glacial sea-level variations has been applied to estimate erosion conditions applying in the past. The conclusion is reached that present conditions are exceptionally favourable for rapid erosion. Early post-glacial marine erosion swept away the glacial drift blanket from the present sea-bed, then erosion of the solid cliff extended the wave-cut foreshore by an average of about seventy feet, this width having been cut down to its present level within the past thousand years. The old cliff foot line, lying about seventy feet from the present cliff, is considered to be of Last (Eemian) Interglacial age.