Mission Areas

Volcano Hazards

Programs L2 Landing Page

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

Volcano Activity Notifications

Volcano Activity Notifications

There are 169 potentially active volcanoes in the United States. USGS Volcano Observatories release regular notifications to communicate increases or decreases in volcanic activity and to explain any unusual or hazardous circumstances.

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Volcano Hazards Assessments

Volcano Hazards Assessments

Long-term hazards assessments identify locations at risk from volcanic hazards. They are released as high-resolution hazards-zonation maps with accompanying explanations, which help guide eruption preparedness plans.

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U.S. Volcano Observatories

Volcano Observatory staff monitor, research, and issue formal notices of activity for volcanoes in assigned geographic areas. Scientists also assess volcano hazards and work with communities to prepare for volcanic eruptions.

Alaska Volcano Observatory (AVO)

USGS California Volcano Observatory (CalVO)

USGS Cascades Volcano Observatory (CVO)

USGS Hawaiian Volcano Observatory (HVO)

Yellowstone Volcano Observatory (YVO)

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News

Turnagain Arm Railway
June 21, 2017

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.

Image shows several insets against the backdrop of Mount St. Helens erupting
May 18, 2017

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.

Side-by-side comparison of the northwest wall of Kīlauea Caldera on a clear day (left) and a day with thick vog (right).
May 18, 2017

Just like smog and fog, this EarthWord is not what you want to see while driving...

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Mount Rainier seen from Puyallup, Washington
March 17, 2016

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.

Redoubt Volcano viewed from the northwest following the April 4, 2009 eruption (Event 19). Steam rises from the summit crater, p
March 7, 2016

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.

Alaska Volcano Observatory logo
March 2, 2016

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.

California Volcano Observatory emblem
March 2, 2016

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.

Mount St. Helens and Mount Rainier, northern aerial view
March 2, 2016

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.

Scientist shields face while scooping lava with a hammer for chemical analysis
March 2, 2016

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.

Yellowstone Volcano Observatory logo
March 2, 2016

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.

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A gas plume arising from Augustine Volcano during it's eruptive phase 2005-06.
April 27, 2016

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.

Screenshot of Volcano Hazards Program website page showing current alerts for U.S. Volcanoes
April 27, 2016

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.

Tephra and gas eruption from Mount St. Helens crater with dome
March 17, 2016

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.

Ash-rich plume rises out of Halemaʻumaʻu Crater, Kilauea Volcano Hawaiʻi
March 4, 2016

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.

March 4, 2016

/data-tools/volcano-notification-service-vns" target="">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.

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Year Published: 2017

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, III, 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.
Bradley, D.C., Miller, M.L., Friedman, R.M., Layer, P.W., Bleick, H.A., Jones, J.V., III, Box, S.E., Karl, S.M., Shew, N.B., White, T.S., Till, A.B., Dumoulin, J.A., Bundtzen, T.K., O’Sullivan, P.B., and Ullrich, T.D., 2017, Regional patterns of Mesozoic-Cenozoic magmatism in western Alaska revealed by new U-Pb and 40Ar/39Ar ages, in Dumoulin, J.A., ed., Studies by the U.S. Geological Survey in Alaska, vol. 15: U.S. Geological Survey Professional Paper 1814–D, 48 p., https://doi.org/10.3133/pp1814D.

Year Published: 2017

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.
Groover, K.D., Burgess, M.K., Howle, J.F., Philips, S.P., 2017, Electrical resistivity investigation of fluvial geomorphology to evaluate potential seepage conduits to agricultural lands along the San Joaquin River, Merced County, California, 2012–13: U.S. Geological Survey Scientific Investigations Report 2016–5172, 39 p., https://doi.org/10.3133/sir20165172.

Year Published: 2015

Global volcanic hazards and risk

Loughlin, 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, M. R.; 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, S.; Andreastuti, S.; Subandriyo, J.; Sumarti, S.; 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.
Attribution: Volcano Hazards

Year Published: 2015

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
Attribution: Volcano Hazards
Thelen, W.A., and Cooper, Jennifer, 2014, An analysis of three new infrasound arrays around Kīlauea Volcano: U.S. Geological Survey Open-File Report 2014–1253, 29 p., http://dx.doi.org/10.3133/ofr20141253.

Year Published: 2014

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.
Attribution: Volcano Hazards

Year Published: 2014

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.
Attribution: Volcano Hazards
Shaking up volcanoes; 2014; Article; Journal; Science; Prejean, Stephanie G.; Haney, Matthew M.

Year Published: 2014

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.
Attribution: Volcano Hazards
Electron microprobe analyses of glasses from Kīlauea tephra units, Kīlauea Volcano, Hawaii; 2014; OFR; 2014-1090; Helz, Rosalind L.; Clague, David A.; Mastin, Larry G.; Rose, Timothy R.

Year Published: 2014

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.
Attribution: Volcano Hazards
Compaction and gas loss in welded pyroclastic deposits as revealed by porosity, permeability, and electrical conductivity measurements of the Shevlin Park Tuff; 2014; Article; Journal; GSA Bulletin; Wright, Heather M.; Cashman, Katharine V.

Year Published: 2013

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
Attribution: Volcano Hazards
Publications of the Volcano Hazards Program 2011; 2013; OFR; 2013-1164; Nathenson, Manuel

Year Published: 2012

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.
Attribution: Volcano Hazards
A mantle-driven surge in magma supply to Kīlauea Volcano during 2003--2007; 2012; Article; Journal; Nature Geoscience; Poland, Michael P.; Miklius, Asta ; Sutton, A. Jeff; Thornber, Carl R.

Year Published: 2011

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
Attribution: Volcano Hazards
Publications of the Volcano Hazards Program 2009; 2011; OFR; 2011-1047; Nathenson, Manuel

Year Published: 2011

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.
Attribution: Volcano Hazards
Segregating gas from melt: an experimental study of the Ostwald ripening of vapor bubbles in magmas; 2011; Article; Journal; Contributions to Mineralogy and Petrology; Lautze, Nicole C.; Sisson, Thomas W.; Mangan, Margaret T.; Grove, Timothy L.

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2017 (approx.)

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, we can speed up the signal and make it audible. Listen to the sound of an earthquake and match it with the event that created it using the spectrogram/seismogram to help. Is the sound from:

  • The 2001 Nisqually earthquake recorded in Sequim, Washington?
  • A rock avalanche at Mount Rainier?
  • Lava spine extrusion at Mount St. Helens?
  • An eruption, gliding tremor and explosion at Mount Redoubt, Alaska?
     
Aerial photo of snow-covered mountaIns with umbrella-shaped volcanic ash plume rising in the background
February 19, 2017

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.

Satellite image of small crescent-shaped ocean island.
January 24, 2017

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 aerial photo of crescent shaped island surrounded by open ocean.
January 10, 2017

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 by Dan Leary, Maritime Helicopters, January 10, 2017.

man standing in room full of equipment, working on box on central work table
October 27, 2016

At the USGS Cascades Volcano Observatory Electronics Lab, technicians build, test, and prepare scientific instruments to be deployed for monitoring volcanoes worldwide.

storage room with rows of steel boxes and cases filling heavy metal shelves
October 27, 2016

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.

close-up of steel cylinder with cables and bright red and yellow caps coming out of it.
October 27, 2016

Seismometers (instruments for recording earthquakes) are tested and fitted at the USGS Cascades Volcano Observatory before going out into the field.

September 29, 2016

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.

August 7, 2016

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 hazards, and modern scientific monitoring technologies. They camped, hiked to field sites, worked on research projects with scientists, and learned how to document and share their scientific findings by building a public webpage. Highlights from the week are showcased in this video. 

The goal of the program is for GeoGirls participants to emerge with a stronger understanding and connection to Earth systems and feel confident in choosing careers in science, technology, engineering, math or other STEM-related fields. 

The program was led by female scientists from the USGS, the Mount St. Helens Institute, UNAVCO, Washington State Department of Natural Resources, University of Washington, Western Washington University and Oregon State University. This is the second summer of the GeoGirls program, which will continue in 2017. 

To apply, visit the Mount St. Helens Institute website.

Woman and girls next to a lake, seiving sediment
2016 (approx.)

 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.

July 28, 2016

Volcanic eruptions occur int he State about as frequently as the large San Andreas Fault Zone earthquakes. California's "watch list" volcanoes are dispersed throughout the State and future eruptions are inevitable—the likelihood of renewed volcanism is on the order of one in a few hundred to one in a few thousand annually.

With Margaret Mangan, Scientist-in-Charge, USGS CalVO

aerial photograph of steaming & smoking lava lake. Orange lava is visible through cracks & spatter in the lake's black crust.
July 27, 2016

 Aerial photograph of active lava lake in Hale maʻumaʻu Crater at the summit of Kīlauea volcano.

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Turnagain Arm Railway
June 21, 2017

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.

Image shows several insets against the backdrop of Mount St. Helens erupting
May 18, 2017

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.

Side-by-side comparison of the northwest wall of Kīlauea Caldera on a clear day (left) and a day with thick vog (right).
May 18, 2017

Just like smog and fog, this EarthWord is not what you want to see while driving...

Image shows billowing clouds of steam and smoke emanating from the ground
May 17, 2017

This EarthWord is straight up steampunk...

Image shows damage from a lahar, including a submerged bridge
May 16, 2017

Which sounds more dangerous, lava or mud? The answer may surprise you...

USGS map displaying potential to experience damage from a natural or human-induced earthquake in 2017
May 15, 2017

It’s not just something you run into on a golf course-it’s this week’s EarthWord!

Image: Old Faithful Erupting
May 10, 2017

Despite two centuries of scientific study, basic questions persist about geysers—why do they exist? What determines their behavior?

Large snow-covered, cone shaped mountain in background, looming over urban area in foreground
May 1, 2017

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.

Annotated aerial photo of crescent shaped island surrounded by open ocean.
March 3, 2017

Bogoslof volcano, located in the Aleutian Islands about 98 km (61 mi) northwest of Dutch Harbor/Unalaska, is in an active eruption sequence that began in mid-December 2016 and continues today.

Mt. Merapi
January 9, 2017

In early September of 2010, a pattern of increased earthquake activity occurred at the Mount Merapi volcano in Indonesia. A few days later, an avalanche was observed south of the mountain, and white plumes were seen rising above the crater. A lava dome detected in March began to increase rapidly.

A gas plume arising from Augustine Volcano during it's eruptive phase 2005-06.
January 4, 2017

How many potentially active volcanoes are there in the United States?

Littoral explosion sends incandescent lava fragments skyward at Kīlauea Volcanoʻs ocean entry, Hawaiʻi
November 9, 2016

For the first time, the United States will host the international Volcano Observatory Best Practices workshop, previously held only in Italy. The workshop will take place from November 15-18 in Vancouver, Washington. It is designed specifically for volcano observatories around the world and their staff to exchange ideas and best practices with each other.