Yellowstone volcano super-eruptions appear to involve multiple explosive events

Aerial view of the Grand Prismatic Spring at Yellowstone National Park, with blue center and orange and yellow at the edges

The last super-eruption at Yellowstone volcano, which occurred 631,000 years ago, was not one huge explosion. Instead, new research suggests it was a series of eruptions or multiple vents spewing volcanic material in rapid succession. 

According to the U.S. Geological Survey's (USGS) Yellowstone Volcano Observatory 2022 Annual Report, published May 4, fieldwork over the past year has provided new geological evidence that "the formation of Yellowstone Caldera was much more complex than previously thought." A caldera is a large crater that forms after the collapse of a volcano following an eruption.