Eruptions at Snake River Plain in Idaho were “significantly larger” than geologists had previously thought.
Scientists from the University of Leicester discovered there were a staggering 12 massive eruptions over the course of four million years, beginning 12 million years ago.
The massive eruptions helped to form the 100 kilometre-wide Snake River Basin, with one of the most powerful eruptions occurring 8.1 million years ago. The eruption’s volume exceeded 1,900 km3 and created a 1.3km thick caldera.
Furthermore, the Snake River Plain is situated on the Yellowstone Hotspot track, a region which spans from Nevada, through Oregon and Idaho and then to Wyoming where Yellowstone Volcano is located.
Dr Tom Knott from the University of Leicester, said: “While it is well-know that Yellowstone has erupted catastrophically in recent times perhaps less widely appreciated is that these were just the latest in a protracted history of numerous catastrophic super-eruptions that have burned a track along the Snake River eastwards from Oregon to Yellowstone from 16 Ma to present.
“The size and magnitude of this newly defined eruption is as large, if not larger, than better known eruptions at Yellowstone, and it is just the first in an emerging record of newly discovered super-eruptions during a period of intense magmatic activity between eight and 12 million years ago.”