Volcano Hazards Program

Cenozoic volcanic rocks of the Arabia Plate cover about 140,000 square kilometers across a distance of about 3,000 kilometers from southern Yemen to southeastern Turkey. The majority of volcanic products are alkali basalts that erupted in restricted areas, commonly over periods of a million or more years, building mafic lava fields, each known in Arabic as a “harrat.” Harrat volcanism...

Introduction Eruptions at Mount Rainier produce lava flows, plumes of airborne volcanic ash, and avalanches of hot rock, ash, and gas—pyroclastic flows—that rush down the steep, ice-covered slopes of the volcano. Hot rock and ash ejected during an eruption can melt large quantities of snow and ice, forming huge, fast moving mudflows called lahars that travel 30+ miles, all the way to...

The Yellowstone Volcano Observatory (YVO) monitors volcanic and hydrothermal activity associated with the Yellowstone magmatic system, carries out research into magmatic processes occurring beneath Yellowstone Caldera, and issues timely warnings and guidance related to potential future geologic hazards. YVO is a collaborative consortium that includes the U.S. Geological Survey (USGS)...