Scientists Uncover Vast Hidden Geological Network Beneath East Antarctica's Ice Sheet

Published June 3, 2026 in Nature Geoscience, the study led by geophysicist Egidio Armadillo of the University of Genoa identifies 30 elongated, wedge-shaped basins beneath ice up to three kilometers thick as components of a single, previously unrecognized geological system. Researchers combined subglacial topography, gravity and magnetic anomaly data from low-altitude airborne surveys, seismic imaging, and lithospheric models to map the structure; Dr. Guy Paxman of the University of Cambridge contributed ice-rebound modeling that reconstructed what East Antarctica's landscape would look like without its ice sheet, revealing the feature's full elevation and orientation. The province may represent one of the largest examples of distributed rotational extension ever identified within continental crust, a process in which crust stretches outward from a fixed Euler pole in a pattern likened to fingers spreading from a hand. Independent geologist John Goodge described the findings as 'provocative,' noting that East Antarctica has long been considered ancient and stable, and suggested the pull-apart basin system could help explain anomalous heat flow and the hundreds of subglacial lakes identified beneath the ice. Because the basins underlie roughly half of the East Antarctic Ice Sheet, the authors warn they are likely to heavily influence ice flow and landscape evolution, and Goodge cautioned that thinner crust and elevated geothermal heat in these zones 'could introduce widespread, systemic instability' to the ice sheet. Subglacial topography maps confirm the structural features, including the Belgica Bisector tectonic boundary, rift systems, and the Gamburtsev Mountains, situating the EAFBP within a complex bedrock landscape. Key open questions remain, including the precise timing of the structure's formation and the full geodynamic sequence that produced it.