Weathering Characteristics of the Glacial Drifts, Bunger Hills, East Antarctica

Abstract

Mapping of glacial drift sheets and examination of striae patterns throughout the Bunger Hills, suggests that the largely ice-free region records the imprint of several phases of ice sheet and outlet glacier expansion during the late Pleistocene. The oldest glacial drift identified in the Bunger Hills is the most extensive, and displays a weathering status that allows its discrimination from the moderately weathered Figurnoe drift. The latter drift is hummocky and preserves a series of high-level paleolake shorelines at the western end of modern Lake Figurnoe. Within the limits of the Figurnoe drift, the Apendiksi drift was mapped on the basis of its degree of morphological preservation and minimal surface and subsurface drift weathering. Lobes of Apendiksi ice extended up to 8 km west of the modern ice sheet margin in the southern Bunger Hills. Advances of the Edisto Glacier are renamed the Edisto 1 to 3 in order of reducing relative age. The morphostratigraphic evidence suggests that the glacial history of the Bunger Hills is more complex than had previously been recognized, and emphasizes the need for detailed glacial geologic work in this and other ice-free coastal areas of eastern Antarctica.