MAMMOTH, Wyo. – The hydrothermal explosion at Yellowstone National Park last summer was caused by a "clogged up" plumbing system, the U.S. Geological Survey (USGS) recently announced.

Officials determined that minerals had formed a seal in the plumbing system underneath the Black Diamond Pool in the Yellowstone's Biscuit Basin, causing pressure to build up just below the surface of the pool.

"An explosion was inevitable," the USGS said.

Footage and photos of the explosion, which occurred on July 23, 2024, show a blast powerful enough to hurl large rocks and other debris hundreds of feet high.

YELLOWSTONE BISCUIT BASIN GEYSER SENDS DEBRIS FLYING, DESTROYS BOARDWALK

The explosion was enough to send park visitors scrambling to safety , as they had stood on a boardwalk that coursed over t

See Full Page