A massive hydrothermal explosion at Yellowstone s Biscuit Basin forced visitors to flee as steam, mud, and debris erupted into the air.
Videos show people running from a large column of grey mud and rocks, with boiling water also being expelled.
The National Park Service reported no injuries but noted damage to nearby boardwalks and benches; the area was closed off.
The US Geological Survey provided images showing the extent of the debris field and explained the hydrothermal explosion as water rapidly turning to steam, causing violent eruptions.
Hydrothermal explosions result from water turning to steam in a shallow system, leading to the ejection of boiling water, steam, mud, and rock fragments.
These explosions, while not volcanic, can cause significant local damage to thermal features and pose hazards.
Biscuit Basin experienced a hydrothermal explosion, ejecting steam and debris.Another explosion in the same area caused significant disruption.