Yellowstone supervolcano could erupt much sooner than predicted, study reveals

Ash from a mega-eruption at Yellowstone would spread across the U.S., covering nearby states such as Wyoming, Idaho, Colorado and Montana in up to three feet of ash, according to a 2014 study of what might happen if a supervolcano erupted, and blanketing the Midwest and other parts of the U.S., killing animals and plants, affecting the power grid and destroying buildings, causing a volcanic winter.

Up to now, scientists thought another supervolcano eruption might not occur for centuries, but a new study by researchers at Arizona State University found it could happen much sooner -- in just decades, according to National Geographic.

The ASU scientists studied minerals in fossilized ash around the volcano and discovered that the critical changes in temperature and composition that would signal an impending eruption occurred in a matter of decades, not centuries, National Geographic reported.

The park basically sits on a giant magma reservoir inside three overlapping calderas, or bowl-shaped depressions formed when an underground magma chamber erupted, Live Science reported.

According to scientists, Yellowstone’s supervolcano has erupted three times. The first eruption occurred just over 2 million years ago. The second blast struck 1.3 million years ago and the last eruption happened 640,000 years ago.

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Arizona State researchers told The New York Times more studies are needed before an absolute conclusion about another supervolcano eruption can be determined.