Measurements of Side-slip at Austerdalsbreen, 1959

Abstract

Measurements have been made using two different methods of the rate at which the glacier Austerdalsbreen is slipping past its side wall at four sites. The rate of slipping varies from site to site in a way which seems to be connected with the details of glacier flow in the neighbourhood, and in all cases is less than the slip previously measured further up-glacier at the foot of one of the ice falls, and is also a smaller fraction (about one sixth) of the flow rate in the centre of the glacier. One of the methods measured the velocity of the last metre of ice, and this method gave movements which were more erratic than the other method, which measured velocity a few metres from the edge. This suggests that protuberances of rock and boulders lodged between the ice and the rock wall cause local variations in flow which are smoothed out in a few metres. The results are discussed in connection with the process of glacial erosion.