Odd “Blobs†Beneath Earth’s Surface Finally Explained
These mysterious regions slow down seismic waves from earthquakes and may give rise to volcanic hotspots
By Dan Robitzski, LiveScience on November 29, 2017
The boundary between the Earth's outermost layer, the crust, and the underlying mantle is speckled with mysterious, blob-like regions. Scientists have long known about these odd pockets, which are called ultralow-velocity zones. They slow down the seismic waves caused by earthquakes and may be the culprit for deep mantle plumes, which can lead to volcanic hotspots like those that created Yellowstone National Park or the Hawai'ian Islands.
https://www.scientificamerican.com/article/odd-ldquo-blobs-rdquo-beneath-earth-rsquo-s-surface-finally-explained/
