Scientists have mapped how Earth’s deepest mantle is being deformed—and the results point to long-lost tectonic plates buried thousands of kilometers underground. Using a massive global dataset of seismic waves, they found that most deformation happens in regions where these ancient slabs are thought to reside. The findings confirm long-standing theories but, for the first time, show the pattern on a global scale. It’s a major step toward understanding how the planet’s interior slowly churns over time.
