Scientists discover giant, fan-shaped structure deep beneath the East Antarctic Ice Sheet

Key Points:

• Scientists have identified a giant, fan-shaped tectonic structure beneath the East Antarctic Ice Sheet, formed by distributed rotational extension, which connects several major subglacial basins including the Wilkes, Aurora, and Lake Vostok basins.
• This structure, named the East Antarctic Fan-Shaped Basin Province, likely developed during the breakup of the ancient supercontinent Gondwana, particularly linked to the separation of Antarctica and Australia around 70 million years ago.
• The discovery challenges the view of East Antarctica as a stable cratonic region, suggesting a more dynamic tectonic history that influenced the formation of large basins, the uplift of the Gamburtsev Mountains, and the breakup of the Transantarctic Mountains.
• The findings open new research directions into the mechanisms driving distributed rotational extension and have implications for understanding how tectonics affect glacier and ice stream behavior under climate change.
• Since over 99% of East Antarctica's bedrock lies hidden beneath ice, the study highlights the importance of integrating multiple geophysical data sources to uncover Antarctica's concealed geological history.