By measuring seismic waves from earthquakes, scientists were able to map the magma chamber underneath the Yellowstone caldera as 55 miles (88.5 kilometers) long, lead author Jamie Farrell of the University of Utah said Monday.
The chamber is 18 miles (29 kilometers) wide and runs at depths from 3 to 9 miles (5 to 14 1/2 kilometers) below the earth, he added.
That means there is enough volcanic material below the surface to match the largest of the supervolcano’s three eruptions over the last 2.1 million years, Farrell said.
The largest blast—the volcano’s first—was 2,000 times the size of the 1980 eruption of Mount St. Helens in Washington state. A similar one would spew large amounts of volcanic material in the atmosphere, where it would circle the earth, he said.
“It would be a global event,” Farrell said. “There would be a lot of destruction and a lot of impacts around the globe.”
The last Yellowstone eruption happened 640,000 years ago, according to the U.S. Geological Survey. For years, observers tracking earthquake swarms under Yellowstone have warned the caldera is overdue to erupt.
Read more at: Phys.org