What triggers a supervolcano eruption? An earthquake? No one really knows. “As a magma chamber of Yellowstone expands, it pushes the roof up and forms faults,” Gregg said in a statement. Patricia Gregg is a volcanologist at the University of Illinois at Urbana-Champaign. “As these very large magma chambers grow, the roof above may become unstable, and it becomes easier to trigger an eruption through faulting or failure within the rock.”
The research team’s model suggests that, if a crack in the roof penetrates the magma chamber, the magma within uses the fault or crack as a vent to shoot to the surface. This could trigger a chain reaction that “unzips” the whole supervolcano, the researchers said. These findings suggest that if supervolcano eruptions are triggered by external factors, such as faults in the roofs of their magma chambers, “then we should look at seismicity, what types of faults are being developed, what is the stability of the roof and what kinds of activities are happening on the surface that could cause faulting,” Gregg said in a statement. –Live Science
The 1959 earthquake in Yellowstone National Park gives us some idea of just how deadly the fault and volcanic system under the park really is.