The blast occurred about 10 a.m. local time near the Black Diamond Pool in Biscuit Basin, about two miles northwest of Old Faithful. No injuries were reported.

“Steam explosions like Tuesday’s incident have long been considered one of the most significant hazards posed to Yellowstone visitors,” says Tony Lowry, associate professor in Utah State University’s Department of Geosciences. “Biscuit Basin has had smaller, but still dangerous, events in the recent past.”

USU alum Jamie Farrell, research associate professor in the University of Utah’s Department of Geology and Geophysics and chief seismologist of the U.S. Geological Survey’s Yellowstone Volcano Observatory, says it was “very lucky” no one was hurt in today’s blast.

“Hydrothermal explosions happen quite frequently in the park, though they often occur in the uninhabited back country," says Farrell, who earned a bachelor’s degree in geology from Utah State in 2001. Farrell says the blasts aren’t volcanic eruptions and no magma is involved.“These incidents occur when very hot, mineral-laden water builds up and clogs the plumbing, so to speak; pressure builds up and is forced upward through pre-existing fractures to erupt at the surface,” he says.