How rivers of hot ash and gas move when a supervolcano erupts

A new study is providing insight into what may happen when one of these colossal entities explodes.The research focuses on the Silver Creek caldera, which sits at the intersection of California, Nevada and Arizona. When this supervolcano erupted 18.8 million years ago, it flooded parts of all three states with river-like currents of hot ash and gas called pyroclastic flows. These tides of volcanic material traveled for huge distances—more than 100 miles.

The new study suggests that pyroclastic flows from the ancient eruption took the form of slow, dense currents—and not fast-moving jets as some experts previously thought. Research on pyroclastic flows is important because it can help inform disaster preparedness efforts, says Valentine, a UB professor of geology and director of the Center for GeoHazards Studies in the UB College of Arts and Sciences.

The research was conducted by Roche at Blaise Pascal University in France, David C. Buesch at the United States Geological Survey and Greg A. Valentine at the University at Buffalo.