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Volcano Hazards Program

Find U.S. Volcano

There are about 170 potentially active volcanoes in the U.S. The mission of the USGS Volcano Hazards Program is to enhance public safety and minimize social and economic disruption from volcanic unrest and eruption through our National Volcano Early Warning System. We deliver forecasts, warnings, and information about volcano hazards based on a scientific understanding of volcanic behavior.

News

Volcano Watch — Distant versus local earthquakes and tsunami response times in Hawaii

Volcano Watch — Distant versus local earthquakes and tsunami response times in Hawaii

Monitoring stations detect small magnitude earthquakes at Mount Rainier during July and August 2025

Monitoring stations detect small magnitude earthquakes at Mount Rainier during July and August 2025

In Memoriam: Wes Hildreth, 1938-2025

In Memoriam: Wes Hildreth, 1938-2025

Publications

Magma fragmentation and tephra deposition from a small-volume phreatomagmatic eruption: Blue Lake crater, Oregon, USA Magma fragmentation and tephra deposition from a small-volume phreatomagmatic eruption: Blue Lake crater, Oregon, USA

Maars pose considerable hazards due to their more explosive nature (compared with more common scoria cones) and likelihood that eruptions produce pyroclastic surges. Blue Lake crater is a maar in the Oregon High Cascades that erupted within the last 3000 years, making it one of the youngest eruptions in the Oregon Cascades. Its young, unaltered deposits make it an excellent site to...
Authors
Sophia Leiter, Pierre-Simon Ross, Emily Johnson

Fluid inclusion constraints on the geometry of the magmatic plumbing system beneath Mauna Loa – Part I: Lavas and tephras Fluid inclusion constraints on the geometry of the magmatic plumbing system beneath Mauna Loa – Part I: Lavas and tephras

There are few petrological constraints on magma storage depths at Mauna Loa, Hawai‘i. Yet understanding the geometry of the magmatic plumbing system is critical for interpreting geophysical signals of unrest at this very high-threat volcano. We address this gap by examining CO₂-rich fluid inclusions (FI) in lava and tephra from seven eruptions (8870 ± 56 14C yr BP, 1852, 1855, 1868, 1949...
Authors
Penny Wieser, Sarah Shi, Matthew Gleeson, Berenise Rangel, Charlotte DeVitre, Alexander Bearden, Kendra Lynn, Marie Camille-Caumon

Rebuilding a volcano one lava flow at a time—Visualizing the lava dome-building eruption in the crater of Mount St. Helens, 1982–1986 Rebuilding a volcano one lava flow at a time—Visualizing the lava dome-building eruption in the crater of Mount St. Helens, 1982–1986

Between 1980 and 1986, the U.S. Geological Survey made a series of 1:2,000-scale topographic contour maps from aerial photographic surveys to monitor the eruption. These maps were made for operational purposes and were not intended for publication. Since then, advances in technology made it possible to digitize the original, highly detailed hardcopy maps and derive new digital data...
Authors
Joseph Bard, Christina Friedle, Lorie Bartee, Brett C. Dierker, Joseph Ganick, Nichola M. Gregory, Kenton R. Hill, Jude G. Klug, Aerial Kruger, Dawson T. Mooney, Reun Morrison, Isa Rojas, Phil Rollo, Shawn Stanton, Bre Stewart, Blair Stuhlmuller, Adam D. Zyla
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