|Posted by George Freund on August 14, 2019 at 10:05 AM|
BY HANNAH OSBORNE ON 8/7/19 AT 8:04 AM EDT
The mantle rock that feeds Yellowstone supervolcano extends all the way to California and Oregon, a scientist has claimed. Victor Camp, a geologist from San Diego State University found there are "finger-like conduits" of mantle that extend westwards, providing magma to distant sites including the volcanic fields of Newberry and Medicine Lake.
Camp also said the mantle rock that sits beneath Yellowstone today appears to have come from the core-mantle boundary that sits deep beneath present-day San Diego. His findings are published in the journal Geology.
Earth is made up of three main layers—the crust, which is the thinnest layer, the mantle, which extends from 62 miles under the surface all the way down to over 1,600 miles, and finally the core. The mantle is made of hot molten rock.
Mantle plumes rise up because they are hotter and lower-density than the surrounding rock. The plume feeding Yellowstone rose up and met the base of the North American tectonic plate, where it was blocked. At this point, the plume melted and started spreading west.
By using seismic tomography images, coupled with data on the volcanic rock at the surface and chemistry, Camp was able to then trace this rock. He found that over millions of years, it spread out through narrow channels, splitting into new branches as it left Yellowstone and again as it got to the border of California and Oregon.