The morning of March 16, 1980, marked the end of 123 years of peaceful solace on the slopes of Mount St. Helens as a series ...

The most recent, 640,000 years ago, was a thousand times the size of the Mount St. Helens eruption in ... all the way to the Gulf of Mexico. Pyroclastic flows—dense, lethal fogs of ash, rocks ...

Saturday marks 44 years since Mount St. Helens erupted ... leaving a downhill flow of pyroclastic material, fragmented rocks and water. These powerful waves of debris are deadly and can be ...

For over a century, geologists were baffled by the rolling mounds scattered across Northern California's Shasta Valley. Travelers along Interstate 5 can glimpse these unusual hills and ridges, often ...

When Mount St Helens erupted in 1980, the resulting lava, ash, and debris turned the landscape barren for miles around. It was clear the land would take a long time to recover from the eruption.