Global seismic map reveals ancient tectonic plates are warping Earth’s mantle near the core

A new global map reveals that ancient tectonic plates buried 2,900km deep are actively deforming Earth's mantle near the core. Researchers used 16 million seismograms to find the "hidden forces."

By: AXL Media

Published: Apr 23, 2026, 8:29 AM EDT

Source: Information for this report was sourced from Seismological Society of America

Mapping the Churn of the Deep Mantle

Deep beneath the Earth's crust, the planet’s interior is far from stagnant. A groundbreaking study published in The Seismic Record has provided the first global-scale view of how the lowermost mantle is being stretched and distorted. By analyzing seismic waves that travel through the deep interior, researchers have identified massive zones of deformation located just above the core-mantle boundary. This mechanical warping is a direct result of mantle convection the slow, churning movement of rock that drives the motion of the tectonic plates we live upon at the surface.

The Discovery of Buried Tectonic Slabs

The research team, led by Jonathan Wolf of the University of California, Berkeley, focused on a layer roughly 2,900 kilometers (1,800 miles) underground. Their map reveals that the most intense deformation occurs in specific regions where ancient tectonic plates are believed to have sunk over millions of years. These "subducted slabs" act as massive intruders in the deep mantle, altering the flow of surrounding material. While geodynamic simulations had previously predicted this relationship, this study offers the first empirical evidence on a global scale, confirming that the "graveyards" of surface plates are still geologically active in the deep interior.

Using Seismograms as a Subterranean Lens

To peer into these extreme depths, scientists analyzed an unprecedented dataset of more than 16 million seismograms gathered from 24 global data centers. When earthquakes occur, they send out shear waves that travel through the mantle and pass into the core. As these waves move through deformed material, they exhibit "seismic anisotropy" a phenomenon where waves travel at different speeds depending on their direction. By measuring these variations, the team was able to pinpoint where the mantle’s fabric has been altered, effectively using earthquake energy to "X-ray" the deepest parts of the planet.