Scientists trace antarctic gravity hole to 70 million years of deep earth shifts

Wednesday 18 February 2026 - 07:50

By: Dakir Madiha

Scientists trace antarctic gravity hole to 70 million years of deep earth shifts

Two new scientific studies are reshaping understanding of Antarctica’s geological past and its potential future, linking slow-moving forces deep within the Earth to the evolution of the continent’s vast ice sheets.

Researchers have traced the origins of Antarctica’s so called gravity hole, the strongest gravitational anomaly on the planet, to rock movements occurring over tens of millions of years. At the same time, an international team has drilled a record breaking sediment core beneath the Antarctic ice, uncovering 23 million years of climate history.

A study published in Scientific Reports by geophysicist Alessandro Forte of the University of Florida and Petar Glišović of the Institut de physique du globe de Paris reconstructed the development of the Antarctic gravity hole across the past 70 million years. Using seismic data and advanced computer modeling, the team mapped how variations in rock density deep beneath the surface shaped the region’s gravitational field.

The researchers found that the gravity anomaly was weaker in the distant past but intensified between roughly 50 and 30 million years ago. That timeframe coincides with major climatic transitions in Antarctica, including the onset of widespread glaciation that ultimately defined the frozen continent seen today.

According to Forte, understanding how processes inside the Earth influence gravity and sea levels offers insight into the factors that may affect the growth and long term stability of massive ice sheets. By comparing physics based reconstructions with satellite gravity measurements, the team identified a close match, strengthening confidence in their models. Future research will explore whether a direct causal relationship exists between the strengthening of the gravity anomaly and the expansion of Antarctic ice sheets.

In parallel, a 29 member international team working under the SWAIS2C project achieved a separate milestone by extracting a 228 meter sediment core from beneath 523 meters of ice at Crary Ice Rise. The drilling site lies about 700 kilometers from the nearest Antarctic base. Until now, the longest sediment cores recovered from beneath an ice sheet measured less than 10 meters.

Molly Patterson, co chief scientist from Binghamton University, said the team exceeded its 200 meter target despite the logistical challenges of operating in one of the most remote regions on Earth. The achievement marks one of the most ambitious subglacial drilling operations conducted on the continent.

Preliminary analysis suggests the core contains shell fragments and marine microfossils, indicating that the area was once covered by open ocean rather than permanent ice. The sediments span approximately 23 million years, including intervals when global temperatures were more than 2 degrees Celsius higher than preindustrial levels.

The core has been transported to Scott Base in New Zealand for detailed examination. Samples will be distributed to scientists involved in the SWAIS2C collaboration worldwide. Johann Klages, a German co coordinator of the project at the Alfred Wegener Institute, said the findings could help answer a central question in climate science: when and under what conditions the West Antarctic Ice Sheet might collapse.

Together, the two studies connect deep Earth dynamics with surface climate evolution, offering new clues about Antarctica’s long term stability in a warming world.