The United States has more than 65 active or potentially active volcanoes, more than those of all other countries except Indonesia and Japan. During the twentieth century, volcanic eruptions in Alaska ...

Experts in volcanology observing the Pacific Northwest have raised fresh alerts regarding various volcanic systems within the Cascade Range that are exhibiting increased seismic and thermal activity.

During volcanic crises, the USGS Hawaiian Volcano Observatory (HVO) plays a pivotal role, sharing information on activity and associated hazards with close partners on the Island of Hawaii, including ...

6 A Vision for the USGS Volcano Hazards Program The committee hopes that if a major eruption were to occur in the United States in the year 2010, the USGS VHP would be prepared to respond in a manner ...