The last eruption from Yellowstone National Park, over two million years ago, appears to have been two smaller eruptions more than 6,000 years apart.
By taking samples from the Huckleberry Ridge Tuff created by the eruptions, scientists have used a ‘rock clock’ dating technique to determine the super-volcano was more active than initially thought.
The first eruption is believed to have ejected 2,200 cubic kilometres of magma and the second eruption ejected 290 cubic kilometres, more than 6,000 years later.
Read more at University of Glasgow