Antarctica, as seen using Google Earth, and a cut to show the interior of the earth, where the mantle (red and dark red) and the core (yellow) are visible. The Amundsen Sea Embayment is indicated by the red rectangle. On the right, a photo reveals one of the GPS sites in the study.
Credit: VR. Barletta, DTU Space at the Technical University of Denmark/Google Earth/Terry Wilson, The Ohio State University