An Ancient Landscape Beneath the East Antarctic Ice Sheet

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Geophysical observations of the subglacial topography of Coats Land reveal a landscape formed by tectonics and fluvial erosion that influenced the formation of the East Antarctic Ice Sheet.

Magnetic anomaly map of the subglacial topography of Coats Land beneath the East Antarctic Ice Sheet, showing variations in the Earth’s magnetic field. The boundaries between high (red) and low (blue) values indicate steep geological surfaces, such as major fault systems. Credit: Paxman et al. [2026], Figure 1d. JGR: Earth Surface

In an article signed by Ann Rowan on Eos.org we read that Earth’s ice sheets are changing rapidly in response to anthropogenic climate change, and these changes are modulated by their basal topography. Visualizing the landscape that lies beneath the East Antarctic Ice Sheet not only allows glaciologists to improve model projections of future ice sheet change, but also provides a glimpse of a landscape hidden beneath ice.

Paxman et al. [2026] used geophysical data and satellite imagery to explore the subglacial structure of Coats Land in East Antarctica. They discovered an ancient landscape shaped across several geological periods. A faulted landscape of troughs and escarpments was formed by tectonic extension during the breakup of the supercontinent Gondwana about 180 million years ago, then eroded by rivers for tens of millions of years to form a gently sloping coastal plain, before the formation of the current Antarctic Ice Sheet around 34 million years ago. Ice flow through this ancient ice sheet was steered by the bed topography and dramatically different to the current configuration.