AFI 02/48_02 - Ice-rafted debris on the Antarctic continental margin and dynamics of the Antarctic Ice Sheet - Vibro gravity cores, and sediments data collected from the Weddell Sea, Marguerite Bay, Feb - March 2002

Ice-rafted (Heinrich) layers in the North Atlantic provide clear evidence that basins of large Quaternary ice sheets have, in the past, exhibited major dynamic instabilities. The presence of large ice sheets on the modern Antarctic continent provides an important opportunity to investigate the deposition of ice-rafted debris in a region where the dynamics of the parent drainage basins are known. The aim of the project was to reconstruct the Late Quaternary dynamics of the Antarctic Peninsula Ice Sheet in Marguerite Bay and to compare sedimentation and IRD records with the Larsen Ice Shelf area, on the other side of the Antarctic Peninsula. Two cruises were undertaken to collect the data. The JR71 (2002) cruise builds on the swath bathymetry and TOPAS survey undertaken on the JR59 (2001) cruise. Successful coring and examination of sediments now on and immediately beneath the sea floor, which provided the deforming bed of the former ice stream, enhanced our understanding
of conditions beneath ice streams.