Visitors at Yellowstone National Park experienced a heart-stopping moment on Tuesday when a hydrothermal explosion rocked Biscuit Basin, sending a towering plume of boiling water, mud, rocks, and steam into the air.
The dramatic scene unfolded near Black Diamond Pool, located approximately two miles northwest of the iconic Old Faithful geyser. A video circulating on social media captured the chaotic scene as tourists fled down the boardwalk from the expanding black cloud.
Remarkably, there were no reported injuries, although the explosion caused damage to the boardwalk, leaving it littered with debris and torn fencing. The Park Service immediately closed Biscuit Basin for safety reasons.
The cause of the explosion was attributed to a hydrothermal event, a common occurrence in Yellowstone’s geologically active landscape. Marianne Karplus, a professor of geological sciences at the University of Texas at El Paso, explained that these explosions occur when underground pressure drops, causing liquid water to rapidly flash into steam. The resulting expansion can trigger violent eruptions.
Yellowstone has a history of hydrothermal explosions, with notable events occurring at Norris Geyser Basin in 1989 and Biscuit Basin in 2009. The U.S. Geological Survey (USGS) noted a smaller event at Norris Geyser Basin in April of this year.
Despite the dramatic footage, the Park Service and USGS classified Tuesday’s eruption as a small one. Hydrothermal explosions can reach heights exceeding a mile and leave craters a mile wide, with larger events occurring every 700 years on average.
NPS / Jacob W. Frank
The park is actively working to enhance monitoring efforts in an attempt to detect these events before they occur, but the dynamic nature of geothermal systems makes them difficult to predict. As Karplus stated, “these types of events are very hard to predict or hard to anticipate.”
The closure of Biscuit Basin serves as a reminder of the powerful and unpredictable forces at play beneath Yellowstone’s surface, underscoring the importance of visitor safety and respect for the park’s natural wonders.
