Drumlins in ice sheet reconstructions, with reference to the western Pennines, northern England

Abstract

Drumlin morphology and distribution can be used to determine the palaeoglaciological conditions under which subglacial bedforms were created by Late Pleistocene ice sheets. Detailed field mapping of part of the large drumlin fields in northern England, in particular the identification of areas of superimposed drumlins, has been shown to be of significance in the delimitation of the ice divide within the area. The overall distribution of the subglacial bedforms has also been used to define the extent of ice streams within this part of the Late Devensian (Dimlington Stadial) ice sheet. Based on the physical principles which underlie the deformational model of drumlin formation and present-day glaciological information on subglacial ice sheet conditions, variations in drumlin morphology have allowed a first attempt at reconstructing areas of high (> 100 kPa) and low (< 20 kPa) basal driving stresses for this part of the ice sheet.