Technologies for retrieving sediment cores in Antarctic subglacial settings

Accumulations of sediment beneath the Antarctic Ice Sheetcontain a range of physical and chemical proxies with the potential to document changes in ice sheethistory and to identify and characterize life in subglacial settings. Retrieving subglacial sediments and sediment cores presents several unique challenges to existing technologies. This paper briefly reviews the history of sediment sampling in subglacial environments. It then outlines some of the technological challenges and constraints in developing the corers being used in sub- ice shelfsettings (e.g. George VI Ice Shelfand Larsen Ice Shelf), under ice streams(e.g. Rutford Ice Stream), at or close to the grounding line (e.g. Whillans Ice Stream) and in subglacial lakesdeep under the ice sheet(e.g. Lake Ellsworth). The key features of the corers designed to operate in each of these subglacial settings are described and illustrated together with comments on their deployment procedures.