A reconnaissance survey of the glaciation of Macquarie Island

Abstract

The paper reviews previous ideas on the glaciation of Macquarie Island and gives an account of glacial landforms observed during a brief visit in 1972. The field evidence indicates that Macquarie Island was not completely overridden in an easterly direction by an ice sheet which developed on a broad submarine shelf to the west as advocated by L.R. Blake (in Mawson 1943). Local plateau, valley and cirque glaciers accumulated in depressions, basins and valleys on the surface of the plateau and at their maximum extent occupied about 40% of the island. A migration of the Antarctic Convergence from 150 - 200 km south of the island to north, of the island would depress sea level temperatures by 3-4 degrees; an amount adequate to account for the modest glaciation of the plateau surface. The majority of plant and animal species probably immigrated prior to the last glaciation, which is of Wisconsin age, and survived in non-glaciated areas of the present island and adjacent shelf to the west.