3-D model shows big body of water in Earth's mantle

One of the most dramatic features in the Wysession et. al global mantle shear-wave attenuation model is a very high-attenuation anomaly at the top of the lower mantle beneath eastern Asia. This anomaly is believed due to water that has been pumped into the lower mantle via the long history of the subduction of oceanic lithosphere — crust and upper mantle — in this region. The left figure is a slice through the earth, showing the attenuation anomalies within the mantle. The location of the slice — red line in the upper right figure — is a map of the seismic attenuation at a depth of roughly 620 miles. In both images, red shows unusually soft and weak rock, and blue shows unusually stiff rock (yellow and white show near-average values). The two figures in the lower right are resolution tests to see if the data have the resolution to retrieve Earth structure in these parts of the Earth. The sharper the black-white transitions are, the better the resolution is. Credit: Washington University in St. Louis