The geology underlying Thwaites Glacier plays a critical role in mediating ice flow in this region yet is extremely poorly known. Using new compilations of airborne radar, magnetic and gravity data, supported by published geological evidence, we have interpreted the subglacial geology of the Thwaites Glacier region. Here we provide the new data compilations, results of 3D inversions and vector components defining the lithological units on our new geological sketch map. British Antarctic Survey (BAS) National Capability contribution to the International Thwaites Glacier Collaboration (ITGC) (TJ), NERC Grant NE/S006621/1 (Geophysical Habitats of Subglacial Thwaites (Ghost)) (BK), Antarctic Science Collaboration Initiative program (Australian Government) (ST), European Space Agency (ESA) 4D Antarctica project (FF).

This gridded dataset contains the revised bathymetry model beneath the Brunt Ice Shelf and Stancomb-Wills Glacier Tongue, Antarctica, The revised bathymetric model integrates existing direct bathymetry observations and free air gravity anomaly data to provide the best possible estimate of sub-ice shelf bathymetry. The input direct bathymetric/topographic observations, observation locations, and the input free air compilation are also available as additional separate grid files. All files are provided in NetCDF format in Antarctic Polar Stereographic (EPSG:3031) projection with a horizontal resolution of 2km. The output bathymetry model (Final_adjusted_topography.nc), input topographic observations (Topographic_value_grid.nc) and input topographic observation coverage (Topographic_observation_coverage.nc) have elevation values of metres, positive upwards. The input free air gravity anomaly grid (Brunt_FAA_compilation_grid.nc) has values of mGal. The bathymetric model was produced for the paper of Hodgson et al., (2019) investigating the past and future dynamics of the Brunt Ice Shelf. The publication reference is; Hodgson, D. A., Jordan, T. A., De Rydt, J., Fretwell, P. T., Seddon, S. A., Becker, D., Hogan, K. A., Smith, A. M., and Vaughan, D. G.: Past and future dynamics of the Brunt Ice Shelf from seabed bathymetry and ice shelf geometry, The Cryosphere Discuss., https://doi.org/10.5194/tc-2018-206, in review, 2018.

Aerogravity data collected as part of the seven nation Antarctica''s Gamburtsev Province (AGAP) expedition during the International Polar Year 2007-2009, and used to acquire a detailed image of the ice sheet bed deep in the interior of East Antarctica. Airborne geophysical methods were used to understand the fundamental structure shrouded beneath Dome A. Two twin Otter aircraft - one BAS, one United States Antarctic Program (USAP)- equipped with ice-sounding radars, laser ranging systems, gravity meters and magnetomemeters, operated from camps located on either side of Dome A. Airborne gravity measurements were acquired using LaCoste and Romberg air-sea gravimeter modified by ZLS Corporation, which is well-proven for Antarctic field work. A land-gravimeter was used to tie the still readings on the aircraft with the absolute gravity value at McMurdo Station.