NewsDaily: Study: Yellowstone magma much bigger than thought

NewsDaily: Study: Yellowstone magma much bigger than thought

HELENA, Mont. (AP) — The hot molten rock beneath Yellowstone National Park is 2 ½ times larger than previously estimated, meaning the park's supervolcano has the potential to erupt with a force about 2,000 times the size of Mount St. Helens, according to a new study.

By measuring seismic waves from earthquakes, scientists were able to map the magma chamber underneath the Yellowstone caldera as 55 miles long, lead author Jamie Farrell of the University of Utah said Monday.

The chamber is 18 miles wide and runs at depths from 3 to 9 miles 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.