Scientists have detected a giant fan-shaped structure buried beneath the East Antarctic Ice Sheet, suggesting the frozen continent may be hiding the geological scars of the breakup that helped separat

Key Points:

• Researchers have identified a giant fan-shaped geological province beneath the East Antarctic Ice Sheet, linking several large subglacial basins into a coherent tectonic structure radiating from near the South Pole.
• Named the East Antarctic Fan-Shaped Basin Province, this formation is believed to be a continent-scale scar from tectonic stretching that contributed to the breakup of the supercontinent Gondwana, particularly the separation of Antarctica and Australia.
• The discovery was made using sub-ice topography, gravity, magnetic, and seismic data, revealing that the basins formed through distributed rotational extension, where the crust stretched and rotated over a broad area rather than splitting along a single fault.
• This tectonic activity may have influenced major Antarctic features such as the uplift of the Gamburtsev Mountains and the segmentation of the Transantarctic Mountains, impacting the continent's geological architecture and ice sheet dynamics.
• Understanding this hidden bedrock structure is crucial for ice-sheet models, as bedrock topography controls glacier flow and stability, and the study offers a new framework to interpret East Antarctica’s geological history despite the challenges posed by its thick ice cover.