Iceberg Plough Marks, Subglacial Bedforms and Grounding Zone Moraines in Prydz Bay Antarctica

Abstract

Prydz Bay is located between 068°E and 078°E on the East Antarctic Margin (Fig. 1). It is the downstream end of the Lambert Glacier-Amery Ice Shelf drainage system and has been the site of major ice streams from the East Antarctic Ice Sheet since the late Eocene-early Oligocene [Hambrey et al., 1991]. The bay has a reverse bathymetric gradient typical of the Antarctic Shelf with water depths of 100 to 200 m over shallow banks on the outer shelf and as great as 1400 m in inner shelf deeps (Fig. 1). Mesoscale features on the floor of Prydz Bay have been imaged by multichannel seismic surveys and echo sounder profilers. The images presented here were gathered using a 3.5 kHz echo sounder [Stagg et al., 1983] and a 10 litre airgun with 24 channel, 2400 m streamer (Table 1).