Yellowstone National Park

An underappreciated geologic hazard in Yellowstone National Park is that of hydrothermal explosions.

Five visitors to Yellowstone National Park escaped with non-life-threatening injuries when the car they were riding in went off the Grand Loop Road and sank into a thermal feature near Roaring Mountain.

Warm water temperatures and low stream flows are leading to fishing closures in some streams in Yellowstone National Park.

In the late 1800s, geologists studying the Great Plains region of the United States puzzled over strange deposits. For example, a "white, flour-like earth" in Nebraska. Although initially thought to be from nearby hot springs, under the microscope it was determined that these deposits, which could be found across the region, were from volcanic ash that had rained down from some huge prehistoric eruption.