Yellowstone might have already experienced its “largest and most cataclysmic event,” prompting the idea that the hot spot might be waning drastically, according to a new study.

What’s going on:

  • Researchers discovered two eruptions from the Yellowstone super-volcano from the last 9 million years, one of which might have been the “volcanic province’s largest and most cataclysmic event,” according to a release.
  • The discovery would mean the intensity of Yellowstone might be dropping off.
  • The study’s leader author, Thomas Knott, said in a statement: “It therefore seems that the Yellowstone hot spot has experienced a three-fold decrease in its capacity to produce super-eruption event. This is a very significant decline.”

What we learned

  • Researchers discovered the super eruptions existed after looking to volcanic deposits in Idaho and Nevada. The deposits revealed the color, age and chemical compositions of all the rocks.
  • The first erupted reportedly happened 9 million years ago. It covered 4,600 square miles, which includes most of modern Idaho.
  • The second eruption was even bigger, hitting 8,900 square miles. That would have likely covered Idaho and Utah. Particles would have went into the air and rained down over the entire U.S., too, the researchers said.
  • This research suggested Yellowstone might not erupt for another 900,000 years since the last eruption was 630,000 years ago.

What other research said

  • In 2017, a study suggested that Yellowstone could erupt faster than predicted, according to Fox News. The study suggested that the supervolcano would not erupt soon, though.