Muddy eruption at Black Diamond Pool in Yellowstone National Park

“Kablooey!” That’s the word U.S. Geological Survey volcanic experts used to describe the muddy eruption that occurred Saturday morning at Black Diamond Pool in Yellowstone National Park. In video shared by the USGS on social media, mud can be seen gushing up and out of the pool at Biscuit Basin just before 9:23 a.m., right in the middle of the park’s favorites, Old Faithful and Grand Prismatic.