AUSTIN (KXAN) – Researchers with the University of Texas have discovered a new layer of the Earth that could reveal new information about tectonic plates. The researchers, led by Junlin Hua, a postdoctoral fellow at UT’s Jackson School of Geosciences, published their findings today in the journal Nature Geosciences.

Plate tectonics, where the giant plates that form the Earth’s crust move, are responsible for earthquakes around the world.

The newly discovered layer is made of molten rock and is about 100 miles beneath the surface, the researchers said. Scientists have found similar patches of rock before.

The layer of molten rock is part of the asthenosphere, the highest layer in the upper mantle. It creates a soft, caramel-like ocean which the plates float on.

Scientists didn’t know why this layer was soft until now. Molten rocks was one theory. Using readings from seismic stations, Hua was able to create a global map of the athenosphere. The map revealed the molten rock layer could be found over half the Earth, in spots where the athenosphere was hottest.

A diagram of the asthenosphere, which aids plate tectonics, where researchers at the UT Austin Jackson School of Geosciences say they detected a global layer of partial melt (shown in speckled red). Credit: Junlin Hua, Jackson School of Geosciences

Using the map, Hua was able to compare it with seismic readings showing tectonic movement. He found that this gooey layer wasn’t influencing tectonic movement.

By ruling out this melt layer, scientists are able to remove a variable from computer models, said paper coauthor Thorsten Becker from the Jackson School.

“This work is important because understanding the properties of the asthenosphere and the origins of why it’s weak is fundamental to understanding plate tectonics,” said coauthor Karen Fischer, a seismologist and professor at Brown University, where Hua began his research.

The research was funded by the National Science Foundation. The UT Oden Institute for Computational Engineering and Sciences, Brown University and Cornell University collaborated on the project.

Later this week, KXAN will speak with Hua about his research and what it means for studying earthquakes around the world.