The Origin of Morainic Deposits and the Characteristics of Glacial Erosion in the Western Sør-Rondane, Antarctica

Abstract

Two types of morainic deposits can be found in western Sør-Rondane mountains: the super-glacial morainic ridge the material of which comes from slope evolution, and the hillocky moraine whose origin is related to shear planes in the glacier and therefore subglacial. A hypothesis of the formation of the hillocky moraine is given and the lithological composition of this deposit allows us to deduce the importance of glacial erosion at the level of the ice falls which frequently exist at the beginning of outlet glaciers where they leave the polar ice sheet. On this step, the role of glacier fluctuations is of importance in relation to a special periglacial process: greenhouse frost shattering.