Researchers have mapped a massive fan-shaped network of basins beneath the East Antarctic Ice Sheet, linking several previously studied features into one large geological structure. The discovery, published in a 2026 study, offers new insights into the continent's tectonic past and its influence on current ice movement.
The structure, named the East Antarctic Fan-shaped Basin Province, includes the Wilkes and Aurora basins along with the basin holding Lake Vostok. It formed through distributed rotational extension of the continental crust, a process tied to the ancient Gondwana supercontinent and the later split between Antarctica and Australia. An international team led by Dr. Egidio Armadillo of the University of Genoa combined subglacial topography, gravity, magnetic, and seismic data to identify the feature. Dr. Guy Paxman of Durham University contributed calculations on how the landscape would appear without the ice sheet. The bedrock shape affects ice flow and subglacial lakes today, which may influence the stability of parts of the ice sheet vulnerable to climate change. The study was supported by the Italian National Antarctic Research Program.