Current Alerts for U.S. Volcanoes

Subscribe to the Volcano Notification Service

Subscribe to our feed

To view the interactive volcano activity map, please visit our home page.

ALASKA VOLCANO OBSERVATORY DAILY UPDATESunday, May 19, 2013 01:16 PM (Sunday, May 19, 2013 21:16 UTC)

PAVLOF VOLCANO (CAVW #1102-03-)
55°25'2" N 161°53'37" W, Summit Elevation 8261 ft (2518 m)
Current Volcano Alert Level: WATCH
Current Aviation Color Code: ORANGE

Seismic tremor, intense elevated surface temperatures, and ash, gas and steam emissions continue at Pavlof Volcano.

A plume of steam, ash, and gas, occasionally reaching up to 22,000 ft. above sea level, and extending primarily southeast from the volcano over the North Pacific Ocean is visible in satellite images today. Pilot reports from this morning also indicate that ash emission continues and ash clouds are rising to 21,000 to 22,000 feet above sea level. Minor to trace amounts of ash fall is likely occurring on the north, east and southeast flanks of the volcano and possibly on parts of Pavlof Bay and adjacent waters southeast of the volcano. Overnight, trace amounts of ash were reported to have fallen on the community of Sand Point (http://dec.alaska.gov/Applications/Air/airtoolsweb/Advisories) and a special weather statement for ash fall was issued for Nelson Lagoon at 10:00 AM AKDT this morning (http://pafc.arh.noaa.gov/pubfcst.php?fcst=WWAK82PAFC).

Seismic activity remains elevated with nearly continuous volcanic tremor being recorded on the local seismic network. Although the activity to date has been characterized by relatively low-energy lava fountaining and ash emission, more energetic explosions could occur without warning at any time that could place ash clouds above 20,000 ft. Depending on wind direction, trace to minor amounts of ash may fall on nearby communities, including Sand Point, Nelson Lagoon, King Cove and Cold Bay. Information about mitigating the effects of volcanic ash can be found on the AVO web page.

CLEVELAND VOLCANO (CAVW #1101-24-)
52°49'20" N 169°56'42" W, Summit Elevation 5676 ft (1730 m)
Current Volcano Alert Level: WATCH
Current Aviation Color Code: ORANGE

Elevated surface temperatures at the summit of Cleveland Volcano were observed in satellite images intermittently over the past 24 hours. AVO has received no reports of ash emission or other indications of eruptive activity over the past 24 hours.

Sudden explosions of blocks and ash are possible with little or no warning. Ash clouds, if produced, could exceed 20,000 feet above sea level. If a large ash-producing event occurs, nearby seismic, infrasound, or volcanic lightning networks should alert AVO staff quickly. However, for some events, a delay of several hours is possible. Cleveland Volcano does not have a local seismic network and is monitored using only distant seismic and infrasound instruments and satellite data.

VOLCANO INFORMATION ON THE INTERNET: http://www.avo.alaska.edu
RECORDING ON THE STATUS OF ALASKA'S VOLCANOES (907) 786-7478

CONTACT INFORMATION:
John Power, Scientist-in-Charge, USGS
jpower@usgs.gov (907) 786-7497

Jeff Freymueller, Coordinating Scientist, UAFGI
jeff.freymueller@gi.alaska.edu (907) 378-7556

The Alaska Volcano Observatory is a cooperative program of the U.S. Geological Survey, the University of Alaska Fairbanks Geophysical Institute, and the Alaska Division of Geological and Geophysical Surveys.

---

AVO Alert Archive Search

CASCADES VOLCANO OBSERVATORY WEEKLY UPDATEFriday, May 17, 2013 1:18 PM PDT (Friday, May 17, 2013 20:18 UTC)

CASCADE RANGE VOLCANOES
Current Volcano Alert Level: NORMAL
Current Aviation Color Code: GREEN

Activity Update: All volcanoes in the Cascade Range of Oregon and Washington are at normal levels of background seismicity. These include Mount Baker, Glacier Peak, Mount Rainier, Mount St. Helens, and Mount Adams in Washington State; and Mount Hood, Mount Jefferson, Three Sisters, Newberry Volcano, and Crater Lake in Oregon.

Recent Observations: Activity at all Cascade Range volcanoes remained at background levels, as measured by seismic, GPS, and, where available, tiltmeter data. There have been some small earthquakes at Mount Rainier, but of a sort familiar to seismologists and not indicative of volcanic unrest.

The U.S. Geological Survey Cascades Volcano Observatory and the University of Washington continue to monitor the Washington and Oregon volcanoes closely and will issue additional updates and changes in alert level as warranted.

For other inquiries please call 360 993-8973.

---

Mount St. Helens Seismic Information
CVO Alert Archive Search

HAWAIIAN VOLCANO OBSERVATORY DAILY UPDATESunday, May 19, 2013 06:25 AM (Sunday, May 19, 2013 16:25 UTC)

This report on the status of Kilauea volcanic activity, in addition to maps, photos, and Webcam images (available at http://hvo.wr.usgs.gov/activity/kilaueastatus.php), was prepared by the USGS Hawaiian Volcano Observatory (HVO). Hawai`i Volcanoes National Park status can be found at http://www.nps.gov/havo/ or 985-6000. All times are Hawai`i Standard Time.

KILAUEA VOLCANO (CAVW #1302-01-)
19°25'16" N 155°17'13" W, Summit Elevation 4091 ft (1247 m)
Current Volcano Alert Level: WATCH
Current Aviation Color Code: ORANGE

Activity Summary: At the summit, tiltmeters recorded weak deflation after midnight while the lava lake level remained steady overnight. At Pu`u `O`o vent in the middle east rift zone, there was no lava activity within the crater but the Kahauale`a II lava flow remained active on the north base of the cone. To the southeast, the Peace Day pali flow remained active on the coastal plain while the main flow branch continued to enter the ocean in at least 2 locations spanning the Hawai`i Volcanoes National Park boundary. Gas emissions remained elevated.

Recent Observations at Kilauea summit: The summit tiltmeter network recorded slowing DI inflationary tilt, with a few very minor dips, that slowed through yesterday and turned into weak deflation after midnight. The summit lava lake rose more slowly and remained fairly steady overnight. The most recent sulfur dioxide emission rate measurement was 700 t/d on May 14, 2013; these values are minimums because the data are acquired close to the vent where the plume is most dense and challenging to fully characterize; new measurements must await the return of moderate trade winds. The plume also contained a very small amount of ash-sized tephra (mostly fresh spatter bits and Pele's hair) that was deposited on nearby surfaces. Seismic tremor levels remained at fairly steady low values.

Five earthquakes were strong enough to be located beneath Kilauea Volcano in the past 24 hours: 1 in the Ka`oiki Pali area west of the summit and 4 on south flank faults. The GPS receivers located on either side of the summit caldera continued recording contraction that started on May 11.

Background: The summit lava lake is within a ~160 m (520 ft) diameter cylindrical vent with nearly vertical sides inset within the east wall and floor of Halema`uma`u Crater. Its level has varied from about 25 m to more than 200 m (out of sight) below the floor of Halema`uma`u Crater. The vent has been mostly active since opening with a small explosive event on March 19, 2008. The surface level of the lava lake has remained mostly below the inner ledge (~31 m or 100 ft below the floor of Halema`uma`u Crater on October 29, 2012) and has risen above and flooded the ledge in October, 2012, and January, 2013 before receding to greater depths. The lake level responds to summit tilt changes with the lake receding during deflation and rising during inflation.

Recent Observations at the middle east rift zone vents: Only glow was seen from the east lava pond and spatter cones on the crater floor. The tiltmeter on the north flank of Pu`u `O`o cone recorded minor fluctuations over weak inflationary tilt. GPS receivers on the north rim and south base of Pu`u `O`o cone recorded very weak contraction over the past few days. The most recent (preliminary) sulfur dioxide emission rate measurement was 300 tonnes/day on April 26, 2013, from all east rift zone sources; these values have ranged between 150 and 450 t/d in 2013; these measurements are made at a greater distance from the sources where the plume is more easily characterized.

There were two sets of lava flows outside Pu`u `O`o cone: the Kahauale`a II lava flow continued to slowly spread to the north and northeast from the base of Pu`u `O`o cone. To the southeast, the Peace Day pali breakout continued with scattered activity across the coastal plain while the main branch of the Peace Day flow continued to enter the ocean at 1 main location just outside the Hawai`i Volcanoes National Park boundary and 1 intermittent location just inside the boundary.

HAZARD ALERT: Lava entering the ocean builds lava deltas. The lava delta and adjacent areas are some of the most hazardous areas on the flow field. Frequent delta/bench collapses give little warning, can produce explosions capable of throwing both dense and molten rocks hundreds of meters (yards) in all directions (inland as well as out to sea), and can produce damaging local waves. The steam plume produced by lava entering the ocean contains fine lava fragments and an assortment of acid droplets that can be harmful to your health. The rapidly changing conditions near the ocean entry have been responsible for many injuries and a few deaths.

Background: The eruption in Kilauea's middle east rift zone started with a fissure eruption on January 3, 1983, and continued with few interruptions at Pu`u `O`o Cone, or temporarily from vents within a few kilometers to the east or west. A fissure eruption on the upper east flank of Pu`u `O`o Cone on Sept. 21, 2011, drained the lava lakes and fed a lava flow (Peace Day flow) that advanced southeast through the abandoned Royal Gardens subdivision to the ocean within Hawai`i Volcanoes National Park in early December 2011. Since late December 2011, the flows have remained intermittently active on the pali and the coastal plain and finally re-entered the ocean starting on November 24, 2012. The Kahauale`a flow, which started from the spatter cone/lava lake at the northeast edge of the Pu`u `o`o crater floor in mid-January, 2013, was dead by late April. In general, activity waxes with inflation and wanes with deflation.

Hazard Summary: East rift vents and flow field - near-vent areas could erupt or collapse without warning with spatter and/or ash being wafted within the gas plume; potentially-lethal concentrations of sulfur dioxide gas may be present within 1 km downwind of vent areas. All recently active lava flows are within Hawai`i Volcanoes National Park, adjacent State land managed by the Department of Land and Natural Resources, and private property; the lava flows do not pose a hazard to any structures not already within the County-declared mandatory evacuation zone. Lava deltas, which can collapse into the ocean without warning, are extremely hazardous and should be avoided (see HAZARD ALERT above). Kilauea Crater - ash and Pele's hair can be carried several kilometers downwind; potentially-lethal concentrations of sulfur dioxide can be present within 1 km downwind.

Viewing Summary: East rift zone flow field - Most of the flow field is within the closed-access Kahauale'a Natural Area Reserve (NAR) and the abandoned Royal Gardens subdivision and can only be viewed from the air. A small part of the western flow field near the coast in within Hawai`i Volcanoes National Park (see below for access info). Under favorable weather conditions, active flows-when present-can be seen from the County Viewing Area at Kalapana (Lava hotline 961-8093). Pu`u `O`o Cone and Kilauea Crater - these areas are within Hawai`i Volcanoes National Park; Park access and viewing information can be found at http://www.nps.gov/havo/planyourvisit/lava2.htm.

Additional Information:

For a definition of volcano alert levels and aviation color codes: http://volcanoes.usgs.gov/activity/alertsystem/index.php

Maps, photos, Webcam views, and other information about Kilauea Volcano are available at http://volcanoes.usgs.gov/hvo/activity/kilaueastatus.php. A daily update summary is available by phone at (808) 967-8862.

A map with details of earthquakes located within the past two weeks can be found at http://hvo.wr.usgs.gov/seismic/volcweb/earthquakes/

HVO Contact Information:

askHVO@usgs.gov

Definitions of Terms Used:

DI tilt event: DI is an abbreviation for 'deflation-inflation' and describes a geophysical event of uncertain volcanic significance. DI events are recorded by tiltmeters at Kilauea summit as an abrupt deflation of up to a few microradians in magnitude lasting several hours (weak DI events) to 2-3 days (strong DI events) followed by an abrupt inflation of approximately equal magnitude. The tilt events are usually accompanied by an increase in summit tremor during the deflation phase. A careful analysis of these events suggests that they may be related to changes in magma supply to a storage reservoir at less than 1 km depth, just east of Halema`uma`u crater. Usually, though not always, these changes propagate through the magma conduit from the summit to the east rift eruption site, as many of the DI events at Kilauea summit are also recorded at a tiltmeter at Pu`u `O`o delayed by several hours. DI events often correlate with lava pulses and/or pauses in the eruption at the Pu`u `O`o/Peace Day vents.

fill-and-drain, rise/fall cycles/events or high lava stands: one of the cyclical behaviors exhibited by the summit lava lake in starting in 2009. An event starts with a rise in lava level, a decrease in high-frequency summit tremor amplitude, and a small decrease in tilt. After a period of minutes to hours, the lava will abruptly drain back to its previous level, seismic tremor amplitude will increase for a short time (a seismic tremor burst), and summit tilt will return to its previous level. Although not measured continuously, spot checks of gas emissions demonstrate that far less gas is released during the high lava stand than during its draining phase suggesting that, during the high lava stand, lava is puffed up with gas trapped by crusts on the lava surface; the gas plume will also get thin and wispy during these cycles returning to more robustness afterward. In 2013, the character of these events has changed and are marked more by a lack of spattering sinks and less by a rise in lava level or tilt change during the low seismic tremor levels.

perched lava lake: a lava lake within a rim that is progressively built up by overflows of lava that have cooled and solidified. The most recent example of a perched lava lake is currently active within Pu`u `O`o maintaining a rim standing several meters (yards) above the crater floor. In many ways, a perched lava lake resembles an above-ground swimming pool. Overflows from the pond add layers to the surrounding crater floor building it higher; the overflows also build up the perched lake rim, continually keeping the lake rim raised above the floor.

mauka, makai: Hawaiian terms for directions relative to the coast - makai or ma kai (toward the coast) and mauka or ma uka (toward the highlands or away from the coast).

pali: Hawaiian term for cliff or precipice.

composite seismic events: is a seismic signal with multiple distinct phases that has been recorded frequently at HVO from the Halema`uma`u Overlook vent area since its explosive opening in March, 2008. For the composite events recorded at Halema`uma`u, we typically see an initial high frequency vibration lasting for a few seconds that have been correlated with rockfalls. This is followed by about 30 seconds of a long-period (LP) oscillation with an approximately 2- to 3-second period. The final phase of the signal is several minutes of a very-long-period (VLP) oscillation with an approximately 25- to 30-second period. The LP signals are interpreted to be from the uppermost portion of the conduit and VLP signals are interpreted to be fluid passing through a deep constriction in the conduit through which lava rises to the pond surface we see in the webcam.

Halema`uma`u Overlook vent: has been difficult to describe concisely. The vent is actually a pit, or crater, in the floor of the larger Halema`uma`u Crater which is, in turn, in the floor of the larger Kilauea caldera or crater - a crater within a crater within a crater. It is easiest to describe as a pit inset within the floor of a crater within a caldera. The pit is about 160 m (525 ft) in diameter at the Halema`uma`u Crater floor, is about 50 m in diameter at a depth of 200 m (660 ft) below the Halema`uma`u Crater floor. From November, 2009, to now, a lava pond surface has been visible in this pit.

glow: light from an unseen source; indirect light.

incandescence: the production of visible light from a hot surface. The term also refers to the light emitted from a hot surface. The color of the light is related to surface temperature. Some surfaces can display dull red incandescence at temperatures as low as 430 degrees Centigrade (806 degrees Fahrenheit). By contrast, molten lava displays bright orange to orange-yellow light from surfaces that are hotter than 900 degrees C (1,650 degrees F).

CD: Hawai`i County Civil Defense

tonne: metric unit equal to 1,000 kilograms, 2,204.6 lbs, or 1.1 English tons.

tephra: all material deposited by fallout from an eruption-related plume, regardless of size.

ash: tephra less than 2 mm (5/64 inches) in size.

microradian: a measure of angle equivalent to 0.000057 degrees.

More definitions with photos can be found at http://volcanoes.usgs.gov/images/pglossary/index.php.

The Hawaiian Volcano Observatory is one of five volcano observatories within the U.S. Geological Survey and is responsible for monitoring volcanoes and earthquakes in Hawai`i.

---

HVO Alert Archive Search

CALIFORNIA VOLCANO OBSERVATORY MONTHLY UPDATESaturday, May 18, 2013 4:44 PM PDT (Saturday, May 18, 2013 23:44 UTC)

Monitored CALIFORNIA VOLCANOES
Current Volcano Alert Level: all NORMAL
Current Aviation Color Code: all GREEN

Activity Update: All volcanoes monitored by CalVO's telemetered, real-time sensor networks exhibit normal levels of background seismicity and deformation. Real-time monitoring networks are in place at Mount Shasta, Medicine Lake Volcano, Clear Lake Volcanic Field, Lassen Volcanic Center, Long Valley Caldera and Mono-Inyo Chain.


Observations for April 1, 2013 (0000h PT) through April 30, 2013 (2359h PT):
Mt Shasta: No earthquakes were detected.
Medicine Lake: One M=1.1 earthquake was detected.
Lassen Volcanic Center: Five earthquakes were detected, all of which were below magnitude 2.0.
Clear Lake Volcanic Field: Eight earthquakes were detected (all less than magnitude 2.0). [Note: Typical high level of seismicity was observed under the Geysers steam field located at the western margin of CLVF. The largest event was M=3.4].
Long Valley Caldera and Mono-Inyo Chain: Thirteen earthquakes were located in the southern part of Long Valley Caldera (all were below magnitude 2.0 ); One M=2.6 earthquake was located on the Mono-Inyo chain near June Lakes. Five earthquakes were detected under Mammoth Mountain (all magnitudes under 2.0) [Note: The typical high level of seismicity was observed south of the caldera in the Sierra Nevada range. The largest event was M=2.4]

The U.S. Geological Survey will continue to monitor these volcanoes closely and will issue additional updates and changes in alert level as warranted. For a definition of alert levels see http://volcanoes.usgs.gov/activity/alertsystem/icons.php.

As part of the U.S. Geological Survey's Volcano Hazards Program, the California Volcano Observatory aims to advance scientific understanding of volcanic processes and lessen the harmful impacts of volcanic activity in the volcanically active areas of California and Nevada. For additional USGS CalVO volcano information, background, images, and other graphics visit http://volcano.wr.usgs.gov/vsc/observatories/calvo.html. For general information on the USGS Volcano Hazard Program http://volcanoes.usgs.gov. Statewide seismic information for California and Nevada can be found at http://earthquake.usgs.gov/earthquakes/recenteqscanv/.

---

CalVO Alert Archive Search

NORTHERN MARIANA ISLANDS WEEKLY UPDATEFriday, May 17, 2013 11:09 AM (Friday, May 17, 2013 01:09 UTC)

Report prepared by the U.S. Geological Survey.

PAGAN VOLCANO (CAVW #0804-17=)
18°7'48" N 145°48' E, Summit Elevation 1870 ft (570 m)
Current Volcano Alert Level: ADVISORY
Current Aviation Color Code: YELLOW

A constant gas and water vapor plume from Pagan was visible in satellite images over the past week. This is typical of recent months of observation of Pagan. An ash alert was issued by the VAAC on May 14, 2013; however, as stated in the alert, no ash was identifiable on the MetSat image. The gas/vapor plume from Pagan on this day appeared more robust and extended further downwind than is typical. The hydrothermal system beneath Pagan may have responded to the M6.8 tectonic earthquake that occurred that day about 75 km to the northwest and ~600 km deep.

Because of this ongoing emission of volcanic gas from Pagan, it remains possible that residents of the CNMI may notice sulfurous odors under certain wind conditions. Additional information about volcanic gas and vog can be found online at this address: http://hvo.wr.usgs.gov/hazards/FAQ_SO2-Vog-Ash/main.html

Pagan Volcano is not monitored with ground-based geophysical instrumentation and the only sources of information are satellite observations and occasional reports from observers who pass by or visit the island. We will continue to evaluate satellite imagery, on-island, and mariner reports when they become available, but because the volcano is not monitored with ground-based instruments, we cannot provide advanced warning of activity.

Access to the island may be restricted by the CNMI government. Contact the EMO for the latest information.

No eruptive activity or significant unrest was detected at other volcanoes in Northern Mariana Islands this week.

CONTACT INFORMATION:
USGS Northern Marianas Duty Scientist (808) 967-8815
http://volcano.wr.usgs.gov/cnmistatus.php

CNMI Emergency Management Office (670) 322-8001
http://www.cnmiemo.gov.mp/

---

NMI Alert Archive Search

YELLOWSTONE VOLCANO OBSERVATORY MONTHLY UPDATEWednesday, May 8, 2013 10:24 AM MDT (Wednesday, May 8, 2013 16:24 UTC)

YELLOWSTONE VOLCANO (CAVW #1205-01-)
44°25'48" N 110°40'12" W, Summit Elevation 9203 ft (2805 m)
Current Volcano Alert Level: NORMAL
Current Aviation Color Code: GREEN

During the month of April 2013, the University of Utah located 126 earthquakes in the Yellowstone National Park region. The largest earthquake occurred about 8 miles north north-west of Lake, WY on April 9, 2013 at 03:33 AM MDT and had a magnitude of 3.1.

April seismicity in Yellowstone was marked by three distinct clusters of episodic earthquakes:

1) 10 events located about 8 miles north-northwest of Lake, WY on April 9, 2013 including the largest event of the month. Two other earthquakes occurred near here on April 20th, 2013.
2) 30 events located about 10 miles East of Grayling, MT, with the largest, a magnitude 1.6, occurring amid a swarm of 19 earthquakes from April 11 - 16.
3) A swarm of 19 earthquakes up to magnitude 2.9, occurred over four hours on April 16, 2013, located about 8 miles southwest of West Thumb, WY. This swarm is part of a larger cluster of 46 events in the Pitchstone Plateau area. The majority of this cluster of seismicity occurred in two time periods, April 7 - 9 (14 events) and April 15 -16 (31 events).

Yellowstone earthquake activity is occurring at normal background levels.

Slow subsidence of the caldera, which began in early 2010, continues. Current deformation patterns at Yellowstone are well within historical norms.

Please see: http://www.uusatrg.utah.edu/ts_ysrp.html for a map of GPS stations in the Yellowstone vicinity. For a graph of daily GPS positions at White Lake, within the Yellowstone caldera, please see: http://pbo.unavco.org/station/overview/WLWY

---
The Yellowstone Volcano Observatory (YVO) provides long-term monitoring of volcanic and earthquake activity in the Yellowstone National Park region. Yellowstone is the site of the largest and most diverse collection of natural thermal features in the world and the first National Park. YVO is one of the five USGS Volcano Observatories that monitor volcanoes within the United States for science and public safety.

YVO Member agencies: USGS, Yellowstone National Park, University of Utah, University of Wyoming, UNAVCO, Inc., Wyoming State Geological Survey, Montana Bureau of Mines and Geology, Idaho Geological Survey

CONTACT INFORMATION:
Jacob Lowenstern, USGS
Scientist-in-Charge, Yellowstone Volcano Observatory
jlwnstrn@usgs.gov

---

YVO Alert Archive Search