A Preliminary Geomorphic Overview of Late Quaternary Glacier Fluctuations in the South Shetland Islands, West Antarctica

Abstract

The timing and extent of glaciations during the Late Quaternary in the South Shetland Islands, WestAntarctica were defined using field mapping, geomorphic analysis and radiocarbon dating. Landforms of glacialerosion and deposition, in particular subglacial meltwater channel erosion, suggest that at least three glaciationsoccurred during the late Quaternary within the study region. During the global LGM, glacial troughs (such as MaxwellBay and Admiralty Bay) were overdeepened by an ice stream moving south from an~1000m-thick ice cap centered onthe present-day continental shelf to the north. This ice was responsible for the subglacial meltwater channel erosion,and glacial polished and striated bedrock on the Fildes Peninsula. The recent local glaciations occurred about 2,000years ago and during Little Ice Age (LIA). During these glaciations, glaciers were less extensive than the previous oneand less erosive as a cold-based ice.