India, April 6 -- A new study led by researchers at the University of Texas at Austin has revealed that an ancient piece of Earth's crust buried deep beneath the Midwest is actively drawing down large sections of today's North American crust into the mantle - a process scientists are calling "cratonic thinning."

Using seismic imaging, scientists observed massive, drip-like formations beneath the central US, suggesting that the lithosphere (Earth's rigid outer layer) is thinning as materials from the base of the continent's ancient core, or craton, sink into the mantle transition zone.

This is the first time researchers have potentially captured cratonic thinning in action, as detailed in a paper published in Nature Geoscience.

Geodynam...