Bathymetry and geological structures beneath the Ross Ice Shelf at the mouth of Whillans Ice Stream, West Antarctica, modeled from ground-based gravity measurements

New gravity data reveal important geologic controls on the location and behavior of the grounding zone of Whillans Ice Stream (WIS), West Antarctica. Grounding zones of ice sheets and contiguous ice shelves are important for understanding ice sheet dynamics, as key processes that influence the grounded ice and its discharge into the ocean occur in these regions. Here, we model the bathymetry and shallow geological structures beneath the Ross Ice Shelf in an embayment of the WIS grounding zone using gravity data collected on the ground, in conjunction with seismic and radar data. We find that the region of shallow ocean water (