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There are 169 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. We accomplish this by delivering effective forecasts, warnings, and information about volcano hazards based on scientific understanding of volcanic processes.Learn About U.S. Volcanoes
The Volcano Hazards Program develops long-range volcano hazards assessments. These includes a summary of the specific hazards, their impact areas, and a map showing ground-hazard zones. The assessments are also critical for planning long-term land-use and effective emergency-response measures, especially when a volcano begins to show signs of unrest.
There are 169 potentially active volcanoes in the U.S., and the USGS Volcano Hazards Program provides warnings of unrest and eruption for these volcanoes. We offer volcano monitoring data, provide maps and geologic information, conduct research how volcanoes work, and engage with community education and outreach.
The AVO is a partnership among the USGS, the Geophysical Institute of the University of Alaska Fairbanks, and the Alaska Division of Geological and Geophysical Surveys. To mitigate volcanic hazards, AVO monitors and studies Alaska's hazardous volcanoes to forecast and record eruptive activity. AVO also monitors volcanic activity in the Commonwealth of the Northern Mariana Islands.
CalVO operates real-time volcano monitoring networks, disseminates forecasts and notifications of significant activity, assesses volcano hazards, researches volcano processes, and works with communities to prepare for volcanic eruptions in California and Nevada. The Observatory is located at USGS offices in Menlo Park, California.
The CVO staff conduct research on many aspects of active volcanism, respond to dangerous volcanic activity in many parts of the world, and maintain a close watch over volcanoes in Washington, Oregon and Idaho. The USGS established CVO in Vancouver, Washington, after the May 18, 1980, eruption of Mount St. Helens.
HVO operates monitoring networks, assesses hazards, and issues notifications of volcanic activity and earthquakes in the State of Hawai‘i. HVO scientists conduct fundamental research on volcanic processes and work to educate the communities at risk. HVO is located in Hawaiʻi Volcanoes National Park on the Island of Hawaii.
Monitors and studies the active geologic processes and hazards of the Yellowstone Plateau volcanic field and its caldera. Yellowstone National Park contains the largest and most diverse collection of natural thermal features in the world. YVO also monitors volcanic activity in Montana, Wyoming, Colorado, Utah, and New Mexico.
Subscribe to Volcano Notification Services
The Volcano Notification Service (VNS) is a free service that sends you notification emails about volcanic activity happening at U.S. monitored volcanoes. You can customize the VNS to deliver notifications for certain volcanoes or a range of volcanoes, and you can also choose the notification types you want to receive. Notifications are issued by the five U.S. Volcano Observatories.
Current Alerts for U.S. Volcanoes
Information about active volcanoes in the United States is derived from the Recent Volcano Observatory Activity Reports generated by the USGS Volcano Hazards Program. NHSS retrieves this information every 12 hours and uses it to refresh the features in the U.S. Volcanoes layer.
Volcano Monitoring Data
Many volcanoes in the U.S. are monitored by arrays of several instruments that detect subtle movements within the earth and changes in gas and water chemistry. The Volcano Hazards Program streams this data to its Volcano Observatories and makes it available on volcano-specific websites.
Current Alerts for U.S. Volcanoes
Volcano-alert notifications are produced by Volcano Observatory scientists based on analysis of data from monitoring networks, direct observations, and satellite sensors. They are issued for both increasing and decreasing volcanic activity and include text about the nature of the unrest or eruption and about potential or current hazards and likely outcomes.
Volcano Notification Service (VNS)
The Volcano Notification Service (VNS) is a free service that sends you notification emails about volcanic activity happening at U.S. monitored volcanoes. You can customize the VNS to deliver notifications for certain volcanoes or a range of volcanoes, and you can also choose the notification types you want to receive.
Regional patterns of Mesozoic-Cenozoic magmatism in western Alaska revealed by new U-Pb and 40Ar/39Ar ages: Chapter D in Studies by the U.S. Geological Survey in Alaska, vol. 15
In support of regional geologic framework studies, we obtained 50 new argon-40/argon-39 (40Ar/39Ar) ages and 33 new uranium-lead (U-Pb) ages from igneous rocks of southwestern Alaska. Most of the samples are from the Sleetmute and Taylor Mountains quadrangles; smaller collections or individual samples are from the Bethel, Candle, Dillingham,...Bradley, Dwight C.; Miller, Marti L.; Friedman, Richard M.; Layer, Paul W.; Bleick, Heather A.; Jones, James V.; Box, Steven E.; Karl, Susan M.; Shew, Nora B.; White, Timothy S.; Till, Alison B.; Dumoulin, Julie A.; Bundtzen, Thomas K.; O'Sullivan, Paul B.; Ullrich, Thomas D.
Electrical resistivity investigation of fluvial geomorphology to evaluate potential seepage conduits to agricultural lands along the San Joaquin River, Merced County, California, 2012–13
Increased flows in the San Joaquin River, part of the San Joaquin River Restoration Program, are designed to help restore fish populations. However, increased seepage losses could result from these higher restoration flows, which could exacerbate existing drainage problems in neighboring agricultural lands and potentially damage crops. Channel...Groover, Krishangi D.; Burgess, Matthew K.; Howle, James F.; Phillips, Steven P.
Global volcanic hazards and riskLoughlin, S. C.; Vye-Brown, C.; Sparks, R.S.J.; Brown, S. K.; Barclay, J.; Calder, E.; Cottrell, E.; Jolly, G.; Komorowski, J.C.; Mandeville, C.; Newhall, C.; Palma, J.; Potter, S.; Valentine, G.; Baptie, B.; Biggs, J.; Crosweller, H. S.; Ilyinskaya, E.; Kilburn, C.; Mee, K.; Pritchard, M.; Jenkins, S. F.; Wilson, T. M.; Magill, C.; Miller, V.; Stewart, C.; Blong, R.; Marzocchi, W.; Boulton, M.; Bonadonna, C.; Costa, A.; Auker, Melanie Rose; Deligne, N. I.; Lindsay, J.M.; Smid, E.; Selva, J.; Sandri, L.; Tonini, R.; Macedonio, G.; Solidum, R.; Hincks, T.; Aspinall, W.; Pallister, J.; Surono; Andreastuti, Supriyati; Subandriyo, J.; Sumarti, Sri; Sayudi, D.; Karume, K.; Horwell, C.; Baxter, P.; Kamanyire, R.; Webley, P.W.; Leonard, G.; Poland, M.; Gottsmann, J.; Ortiz Guerrero, N.; Delgado Granados, H.; Lombana Criollo, C.; Wagner, K.; Ogburn, S.E; Wadge, G.; Stone, J.; Marti, J.; Ramon, P.; Mothes, P.; Mandeville, Charles W.; Brown, S. K.; Loughlin, S. C.; Sparks, R.S.J.; Vye-Brown, C.; Barclay, J.; Calder, E.; Cottrell, E.; Jolly, G.; Komorowski, J.C.; Mandeville, C.; Newhall, C.; Palma, J.; Potter, S.; Valentine, G.
An analysis of three new infrasound arrays around Kīlauea Volcano
A network of three new infrasound station arrays was installed around Kīlauea Volcano between July 2012 and September 2012, and a preliminary analysis of open-vent monitoring has been completed by Hawaiian Volcano Observatory (HVO). Infrasound is an emerging monitoring method in volcanology that detects perturbations in atmospheric pressure at...Thelen, Weston A.; Cooper, Jennifer
Sulfur isotope fractionation between fluid and andesitic melt: An experimental study
Glasses produced from decompression experiments conducted by Fiege et al. (2014a) were used to investigate the fractionation of sulfur isotopes between fluid and andesitic melt upon magma degassing. Starting materials were synthetic glasses with a composition close to a Krakatau dacitic andesite. The glasses contained 4.55–7.95 wt% H2O, ∼140...Fiege, Adrian; Holtz, François; Shimizu, Nobumichi; Mandeville, Charles W.; Behrens, Harald; Knipping, Jaayke L.
Shaking up volcanoes
Most volcanic eruptions that occur shortly after a large distant earthquake do so by random chance. A few compelling cases for earthquake-triggered eruptions exist, particularly within 200 km of the earthquake, but this phenomenon is rare in part because volcanoes must be poised to erupt in order to be triggered by an earthquake (1). Large...Prejean, Stephanie G.; Haney, Matthew M.
Electron microprobe analyses of glasses from Kīlauea tephra units, Kīlauea Volcano, Hawaii
This report presents approximately 2,100 glass analyses from three tephra units of Kīlauea Volcano: the Keanakākoʻi Tephra, the Kulanaokuaiki Tephra, and the Pāhala Ash. It also includes some new analyses obtained as part of a re-evaluation of the MgO contents of glasses in two of the three original datasets; this re-evaluation was conducted to...Helz, Rosalind L.; Clague, David A.; Mastin, Larry G.; Rose, Timothy R.
Compaction and gas loss in welded pyroclastic deposits as revealed by porosity, permeability, and electrical conductivity measurements of the Shevlin Park Tuff
Pyroclastic flows produced by large volcanic eruptions commonly densify after emplacement. Processes of gas escape, compaction, and welding in pyroclastic-flow deposits are controlled by the physical and thermal properties of constituent material. Through measurements of matrix porosity, permeability, and electrical conductivity, we provide a...Wright, Heather M.; Cashman, Katharine V.
Publications of the Volcano Hazards Program 2011
The Volcano Hazards Program of the U.S. Geological Survey (USGS) is part of the Geologic Hazards Assessments subactivity, as funded by Congressional appropriation. Investigations are carried out by the USGS and with cooperators at the Alaska Division of Geological and Geophysical Surveys, University of Alaska Fairbanks Geophysical Institute,...Nathenson, Manuel
A mantle-driven surge in magma supply to Kīlauea Volcano during 2003--2007
The eruptive activity of a volcano is fundamentally controlled by the rate of magma supply. At Kīlauea Volcano, Hawai‘i, the rate of magma rising from a source within Earth’s mantle, through the Hawaiian hotspot, was thought to have been relatively steady in recent decades. Here we show that the magma supply to Kīlauea at least doubled during 2003...Poland, Michael P.; Miklius, Asta; Sutton, A. Jeff; Thornber, Carl R.
Publications of the Volcano Hazards Program 2009
The Volcano Hazards Program of the U.S. Geological Survey (USGS) is part of the Geologic Hazards Assessments subactivity as funded by congressional appropriation. Investigations are carried out in the USGS and with cooperators at the Alaska Division of Geological and Geophysical Surveys, University of Alaska Fairbanks Geophysical Institute,...Nathenson, Manuel
Segregating gas from melt: an experimental study of the Ostwald ripening of vapor bubbles in magmas
Diffusive coarsening (Ostwald ripening) of H2O and H2O-CO2 bubbles in rhyolite and basaltic andesite melts was studied with elevated temperature–pressure experiments to investigate the rates and time spans over which vapor bubbles may enlarge and attain sufficient buoyancy to segregate in magmatic systems. Bubble growth and segregation are also...Lautze, Nicole C.; Sisson, Thomas W.; Mangan, Margaret T.; Grove, Timothy L.
In March 2008, a new volcanic vent opened within Halema‘uma‘u, a crater at the summit of Kīlauea Volcano in Hawaiʻi Volcanoes National Park on the Island of Hawaiʻi. This new vent is one of two ongoing eruptions on the volcano. The other is on Kīlauea’s East Rift Zone, where vents have been erupting nearly nonstop since 1983. The duration of these simultaneous summit and rift zone eruptions on...
Seismometers record vibrations from a wide assortment of ground motion events. Each event type has a distinctive ground-motion signal with unique frequency and amplitude—its own seismic signature. Seismologists are trained to identify the source of seismic events seen on a webicorder based on its ‘seismic signature’. Although most ground vibrations have a frequency too low for human hearing,...
February 19 Bogoslof eruption plume as seen from Unalaska Island, 53 miles ESE of Bogoslof volcano. Photo taken from helicopter during fieldwork by AVO geologists at 5:22PM, approximately 14 minutes after the start of the eruption.
Analysis of shoreline changes at Bogoslof volcano due to eruptive activity between January 11 and 24, 2017. The base image is a Worldview-2 satellite image collected on January 24, 2017. The approximate location of the shoreline on January 11, 2017 is shown by the dashed orange line.
Annotated photograph of Bogoslof Island showing the cumulative effects of 2016-17 eruptive activity. A layer of fine muddy appearing ash drapes most of the landscape and covers pre-existing vegetation. The dashed line indicates the area excavated by explosive eruptive activity so far. A prominent zone of upwelling is probably the surface expression of a shallow submarine vent. Photograph taken...
At the USGS Cascades Volcano Observatory Electronics Lab, technicians build, test, and prepare scientific instruments to be deployed for monitoring volcanoes worldwide.
The Volcano Distater Assistance Program (VDAP) maintains an equipment cache located at the USGSS Cascades Volcano Observatory. The volcano monitoring equipment can be rapidly deployed worldwide when needed.
Remembering Mount Pinatubo 25 Years Ago: A look back at one of the largest volcanic eruptions of the 20th century. There was a special showing of the NOVA film "In the Path of a Killer Volcano" at this event which is not present in this video due to copyright issues. Following the viewing, however, USGS Geologist John Ewert (was who featured in the film) answered questions.
Twenty middle-school girls from Washington and Oregon participated in the 2016 “GeoGirls” outdoor volcano science program at Mount St. Helens, jointly organized by the U.S. Geological Survey and the Mount St. Helens Institute.
The GeoGirls spent five days conducting hands-on research and interacting with scientists, educators, and older students, learning about volcanoes, natural...
Led by USGS scientist Cynthia Gardner, GeoGirls collect and sort sediments from the shore of Coldwater Lake, near Mount St. Helens, examining evidence of the May 18, 1980 landslide that dammed Coldwater Creek to create the lake.
With hurricanes in the east and wildfires in the west, natural hazards have the potential to impact a majority of Americans every year. USGS science provides part of the foundation for emergency preparedness whenever and wherever disaster strikes.
Join volcano scientists from around the world during scientific meeting and associated public event in Portland.
True or False: Lightning that takes place during a volcanic eruption is the same as lightning that occurs during a thunderstorm?
Subsurface magma intrusions (sills), rather than surface lava flows, may have triggered the Earth’s most catastrophic extinction event approximately 252 million years ago.
Subduction zone events pose significant threats to lives, property, economic vitality, cultural and natural resources and quality of life. The tremendous magnitudes of these events are unique to subduction zones, and they can have cascading consequences that reverberate around the globe.
Today, in 1980, Mount St. Helens unleashed the most devastating eruption in U.S. history. Two years later, USGS founded the Cascades Volcano Observatory to monitor Mount St. Helens and all the Cascades Volcanoes.
Just like smog and fog, this EarthWord is not what you want to see while driving...
This EarthWord is straight up steampunk...
Which sounds more dangerous, lava or mud? The answer may surprise you...
It’s not just something you run into on a golf course-it’s this week’s EarthWord!
Despite two centuries of scientific study, basic questions persist about geysers—why do they exist? What determines their behavior?
May is Volcano Preparedness Month in Washington, providing residents an opportunity to become more familiar with volcano hazards in their communities and learn about steps they can take to reduce potential impacts.