University of Florida Geophysicists Map Ancient Antarctic "Gravity Hole" Linked to Deep Mantle Rock Shifts and Glaciation

University of Florida researchers link Antarctica's "gravity hole" to deep mantle rock shifts that occurred as the continent's ice sheets first formed.

By: AXL Media

Published: Mar 7, 2026, 6:25 AM EST

Source: The information in this article was sourced from University of Florida

The Reality of Fluctuating Gravitational Pull

While gravity is often perceived as a universal constant, it actually exhibits subtle variations across the Earth's surface. According to a study from the University of Florida published in Scientific Reports on March 7, 2026, the weakest point of this gravitational field is located directly beneath Antarctica. This "gravity hole" is not a literal void but a region where the pull of gravity is slightly lower than the global average. This phenomenon is dictated by the distribution of mass far below the crust, where the density of rock determines the strength of the tug felt at the surface.

Deep Earth Dynamics and Seawater Displacement

The formation of the Antarctic gravity hole is the result of extremely slow movements of rock within the Earth’s mantle occurring over tens of millions of years. According to Dr. Alessandro Forte, a professor of geophysics, these deep-seated shifts have a tangible impact on the planet’s oceans. Because gravity is weaker in this zone, seawater is naturally drawn toward regions with a stronger gravitational pull. Consequently, the sea-surface height surrounding Antarctica sits measurably lower relative to the Earth's center than it would if gravity were uniform, a factor that complicates our understanding of global sea-level rise and orbital mechanics.

Seismic Tomography as a Planetary CT Scan

To map this invisible phenomenon, researchers employed a technique comparable to a medical CT scan, substituting X-rays with earthquake waves. By analyzing how these waves travel through the planet’s interior, Dr. Forte and Dr. Petar Glišović were able to illuminate the three-dimensional structure of the mantle. These earthquake recordings, combined with physics-based computer modeling, allowed the team to create a high-resolution gravitational map. The accuracy of this model was subsequently confirmed by cross-referencing the data with highly precise satellite measurements of the Earth's gravity field.