Some Observations of Differential Ice-Movements on Mikkaglaciären

Abstract

Measurements were made of differential movements and of absolute horizontal-movement vectors during periods of about two weeks in August 1964. Absolute movement was determined by theodolite, and the calculated margins of error were tested against tape measurements. Differential movements were investigated at single crevasses and at some sites along a surface-moraine string. The measurements of movement vectors show a relatively large lateral component of glacier movement in the lee of a sharp bend on the eastern margin. The velocity gradient of the movement component in the glacier's main direction was found to increase locally in connection with the surface moraine. Tape measurements of differential movements at crevasses show slight tendencies to compression and extension in different parts of the glacier tongue.