Subglacial sediments: A regional geological template for ice flow in West Antarctica

We use aerogeophysical data to estimate the distribution of marine subglaci al sediments and fault-bounded sedimentary basins beneath the West Antarcti c Ice Sheet (WAIS). We find that significant ice flow occurs exclusively in regions covered by subglacial sediments. The onsets and lateral margins of ice streams coincide with the limit of marine sediments. Lateral margins a re also consistently linked with fault-bounded basins. We predict that the inland migration of ice streams B and C-1 towards the ice divide outside th e region covered by marine or rift sediments is unlikely. The subglacial ge ology has the potential to modulate the dynamic evolution of the ice stream s and the WAIS.