Abstract

The Aleutian Islands are a volcanic arc that extends 1,800 kilometers west from the Alaska Peninsula. Ice caps developed over the inner islands and the adjacent Aleutian platform during late Wisconsin time, coalescing to form the westernmost part of the Cordilleran ice sheet. At the glacial maximum, the axis of ice dispersal lay south of the islands, causing ice to flow north across the platform and probably to terminate as a floating ice shelf in the southern Bering Sea. During deglaciation, which was initiated at some time prior to 11,000 years B.P., ice caps withdrew from the lowlands and alpine glaciers gradually receded toward the higher volcanic peaks. An apparent early Holocene glacial readvance at Cold Bay on the Alaska Peninsula may have been a unique event; it has no known correlative on any of the islands. Alpine glaciers on higher peaks readvanced at some time during the last 3,000 years.