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Smithsonian / USGS Weekly Volcanic Activity Report

Weekly Volcanic Activity Map

The Weekly Volcanic Activity Report is a cooperative project between the Smithsonian's Global Volcanism Program and the US Geological Survey's Volcano Hazards Program. Updated by 2300 UTC every Wednesday, notices of volcanic activity posted on these pages are preliminary and subject to change as events are studied in more detail.

This is not a comprehensive list of all of Earth's volcanoes erupting during the week, but rather a summary of activity that meet criteria discussed in detail in the "Criteria and Disclaimers" section. Carefully reviewed, detailed narratives on various volcanoes are published as reports of the Bulletin of the Global Volcanism Network.

Smithsonian / USGS Weekly Volcanic Activity Report for the week of 11 May-17 May 2005
Name Location Eruption Start Date Report Status
Bagana Bougainville (Papua New Guinea) 2000 Feb 28 (in or before) New
Dieng Volcanic Complex Central Java (Indonesia) New
Fernandina Ecuador New
Anatahan Mariana Islands (USA) Continuing
Awu Sangihe Islands (Indonesia) Continuing
Bezymianny Central Kamchatka (Russia) 2010 May 21 (?) Continuing
Colima Mexico Continuing
Fuego Guatemala 2002 Jan 4 Continuing
Kanlaon Philippines Continuing
Karymsky Eastern Kamchatka (Russia) Continuing
Kilauea Hawaiian Islands (USA) 2020 Dec 20 Continuing
Klyuchevskoy Central Kamchatka (Russia) 2019 Apr 9 Continuing
Pacaya Guatemala 2015 Jun 7 ± 1 days Continuing
Santa Maria Guatemala 1922 Jun 22 Continuing
Sheveluch Central Kamchatka (Russia) 1999 Aug 15 Continuing
Soufriere Hills Montserrat Continuing
Spurr United States Continuing
St. Helens United States Continuing
Weekly Reports Archive

Since the Weekly Volcanic Activity Report began in November 2000, there have been 16,647 individual reports over 1,062 weeks (average of 16 per week) on 312 different volcanoes.

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Agung Copahue Ijen Little Sitkin Pelee South Sarigan Seamount
Ahyi Cotopaxi Iliamna Llaima Peuet Sague Spurr
Aira Cuicocha Iliwerung Loihi Pinatubo St. Helens
Akan Cumbal Inielika Lokon-Empung Planchon-Peteroa Stromboli
Alaid Dabbahu Ioto Lopevi Poas Sulu Range
Alu-Dalafilla Dempo Irazu Machin Popocatepetl Sumbing
Ambae Descabezado Grande Iya Makian Puyehue-Cordon Caulle Sundoro
Ambang Dieng Volcanic Complex Izu-Torishima Makushin Rabaul Suretamatai
Ambrym Dukono Jackson Segment Maly Semyachik Raikoke Suwanosejima
Anatahan Ebeko Kaba Manam Ranakah Taal
Antillanca Volcanic Complex Ebulobo Kadovar Manda Hararo Raoul Island Tair, Jebel at
Antuco Egon Kambalny Marapi Rasshua Takawangha
Apoyeque Ekarma Kanaga Maroa Raung Talang
Arenal Epi Kanlaon Martin Redoubt Tambora
Asamayama Erebus Karangetang Masaya Reventador Tanaga
Askja Erta Ale Karkar Maule, Laguna del Reykjanes Tandikat-Singgalang
Asosan Etna Karthala Mauna Loa Rincon de la Vieja Tangkoko-Duasudara
Augustine Etorofu-Yakeyama [Grozny Group] Karymsky Mayon Rinjani Tangkuban Parahu
Avachinsky Eyjafjallajokull Kasatochi McDonald Islands Ritter Island Tara, Batu
Awu Fernandina Katla Melimoyu Rotorua Telica
Axial Seamount Fogo Katmai Merapi Ruang Tenerife
Azul, Cerro Fonualei Kavachi Midagahara Ruapehu Tengger Caldera
Azumayama Fournaise, Piton de la Kelimutu Misti, El Ruiz, Nevado del Three Sisters
Bagana Fourpeaked Kelut Miyakejima Sabancaya Tinakula
Balbi Fuego Kerinci Momotombo Sakar Tofua
Bamus Fujisan Ketoi Monowai Salak Tokachidake
Banda Api Fukutoku-Oka-no-Ba Kharimkotan Montagu Island San Cristobal Tolbachik
Bardarbunga Galeras Kick 'em Jenny Moyorodake [Medvezhia] San Miguel Toliman
Barren Island Galunggung Kikai Mutnovsky San Vicente Tongariro
Batur Gamalama Kilauea Myojinsho Sangay Tungurahua
Bezymianny Gamkonora Kirishimayama Nabro Sangeang Api Turrialba
Bogoslof Gareloi Kizimen Negra, Sierra Santa Ana Ubinas
Brava Gaua Klyuchevskoy Negro, Cerro Santa Maria Ugashik-Peulik
Bristol Island Gorely Kolokol Group Nightingale Island Sarigan Ukinrek Maars
Bulusan Great Sitkin Korovin Nishinoshima Sarychev Peak Ulawun
Calbuco Grimsvotn Koryaksky Nisyros Saunders Unnamed
Callaqui Guagua Pichincha Krakatau Novarupta Semeru Unnamed
Cameroon Guallatiri Krummel-Garbuna-Welcker NW Rota-1 Semisopochnoi Veniaminof
Campi Flegrei del Mar di Sicilia Guntur Krysuvik-Trolladyngja Nyamulagira Seulawah Agam Villarrica
Cayambe Hachijojima Kuchinoerabujima Nyiragongo Sheveluch West Mata
Cereme Hakoneyama Kurikomayama Okataina Shishaldin Westdahl
Chachadake [Tiatia] Heard Kusatsu-Shiranesan Okmok Simbo Whakaari/White Island
Chaiten Hekla Kverkfjoll Ontakesan Sinabung Witori
Chiginagak Helgrindur Lamington Oraefajokull Sinarka Wolf
Chikurachki Hierro Lamongan Osorno Siple Yasur
Chiles-Cerro Negro Hokkaido-Komagatake Langila Pacaya Sirung Zaozan [Zaosan]
Chillan, Nevados de Home Reef Lanin Pagan Slamet Zavodovski
Chirinkotan Hood Lascar Palena Volcanic Group Snaefellsjokull Zhupanovsky
Chirpoi Huaynaputina Lateiki Paluweh Soputan Zubair Group
Cleveland Hudson, Cerro Lengai, Ol Doinyo Panarea Sorikmarapi
Colima Huila, Nevado del Leroboleng Papandayan Sotara
Colo Hunga Tonga-Hunga Ha'apai Lewotobi Parker Soufriere Hills
Concepcion Ibu Lewotolok Pavlof Soufriere St. Vincent
 News Feeds and Google Placemarks


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The RSS (Really Simple Syndication) feed is identical to the Weekly Volcanic Activity Report minus some features including the header information (latitude and longitude and summit elevation), the Geologic Summary, and a link to the volcano's page from the Global Volcanism Program. At the end of each report is a list of the sources used. Each volcano report includes a link from the volcano's name back to the more complete information in the Weekly Volcanic Activity Report on the Smithsonian website. This feature was first made available on 5 March 2008.



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A Google Earth network link for the Weekly Volcanic Activity Report can be loaded into the free Google Earth software, and in turn will load placemarks for volcanoes in the current weekly report. Placemark balloons include the volcano name, report date, report text, sources, and links back to the GVP volcano profile page and to the complete Weekly Report for that week. This feature was first made available on 1 April 2009.

 Criteria & Disclaimers

Criteria



The Weekly Volcanic Activity Report does not necessarily include all volcanic activity that occurred on Earth during the week. More than a dozen volcanoes globally have displayed more-or-less continuous eruptive activity for decades or longer, and such routine activity is typically not reported here. Moreover, Earth's sea-floor volcanism is seldom reported even though in theory it represents the single most prolific source of erupted material. The Weekly Volcanic Activity Report summarizes volcanic activity that meets one or more of the following criteria:

- A volcano observatory raises or lowers the alert level at the volcano.
- A volcanic ash advisory has been released by a volcanic ash advisory center (VAAC) stating that an ash cloud has been produced from the volcano.
- A verifiable news report of new activity or a change in activity at the volcano has been issued.
- Observers have reported a significant change in volcanic activity. Such activity can include, but is not restricted to, pyroclastic flows, lahars, lava flows, dome collapse, or increased unrest.

Volcanoes are included in the "New Activity/Unrest" section of the Weekly Volcanic Activity Report if the activity occurs after at least 3 months of quiescence. Once a volcano is included in the "New Activity/Unrest" section, updates will remain in that section unless the activity continues for more than 1 month without escalating, after which time updates will be listed in the "Continuing Activity" section. Volcanoes are also included in the "New Activity/Unrest" section if the volcano is undergoing a period of relatively high unrest, or increasing unrest. This is commonly equal to Alert Level Orange on a scale of Green, Yellow, Orange, Red, where Red is the highest alert. Or alert level 3 on a scale of 1-4 or 1-5.

It is important to note that volcanic activity meeting one or more of these criteria may occur during the week, but may not be included in the Weekly Volcanic Activity Report because we did not receive a report.

Disclaimers



1. The Weekly Volcanic Activity Report is intended to provide timely information about global volcanism on a weekly basis. Consequently, the report is generated rapidly by summarizing volcanic reports from various sources, with little time for fact checking. The accuracy of the Weekly Volcanic Activity Report is dependent upon the quality of the volcanic activity reports we receive. Reports published in the Bulletin of the Global Volcanism Network are monthly, and more carefully reviewed, although all of the volcanoes discussed in the Weekly Volcanic Activity Report are not necessarily reported in the Bulletin. Because of our emphasis on rapid reporting on the web we have avoided diacritical marks. Reports are updated on the Weekly Volcanic Activity Report web page as they are received, therefore information may be included regarding events that occurred before the current report period.

2. Rapidly developing events lead to coverage that is often fragmentary. Volcanoes, their eruptions, and their plumes and associated atmospheric effects are complex phenomena that may require months to years of data analysis in order to create a comprehensive summary and interpretation of events.

3. Preliminary accounts sometimes contain exaggerations and "false alarms," and accordingly, this report may include some events ultimately found to be erroneous or misleading.

4. Many news agencies do not archive the articles they post on the Internet, and therefore the links to some sources may not be active. To obtain information about the cited articles that are no longer available on the Internet contact the source.

5. USGS Disclaimer Statement for this Website:

Information presented on this website is considered public information and may be distributed or copied. Use of appropriate byline/photo/image credit is requested. We strongly recommend that USGS data be acquired directly from a USGS server and not through other sources that may change the data in some way. While USGS makes every effort to provide accurate and complete information, various data such as names, telephone numbers, etc. may change prior to updating. USGS welcomes suggestions on how to improve our home page and correct errors. USGS provides no warranty, expressed or implied, as to the accuracy, reliability or completeness of furnished data.

Some of the documents on this server may contain live references (or pointers) to information created and maintained by other organizations. Please note that USGS does not control and cannot guarantee the relevance, timeliness, or accuracy of these outside materials.

For site security purposes and to ensure that this service remains available to all users, this government computer system employs software programs to monitor network traffic to identify unauthorized attempts to upload or change information, or otherwise cause damage. Unauthorized attempts to upload information or change information on this website are strictly prohibited and may be punishable under the Computer Fraud and Abuse Act of 1986 and the National Information Infrastructure Protection Act. Information may also be used for authorized law enforcement investigations. (Last modified September 21, 1999.)

U.S. Department of the Interior, U.S. Geological Survey, Reston, VA, USA
URL: https://volcano.si.edu/reports_weekly.cfm

 Acronyms and Abbreviations

a.s.l. - above sea level

AVO - Alaska Volcano Observatory

AVHRR - Advanced Very High Resolution Radiometer

CENAPRED - Centro Nacionale de Prevencion de Desastres (México)

CONRED - Coordinadora Nacional para la Reducción de Desastres

COSPEC - Correlation Spectrometer

CVGHM (formerly VSI) - Center of Volcanology and Geological Hazard Mitigation

CVO - Cascades Volcano Observatory (USGS)

GMS - Geostationary Meteorological Satellite

GOES - Geostationary Operational Environmental Satellite

GVO - Goma Volcano Observatory

GVP - Global Volcanism Program (Smithsonian Institution)

HVO - Hawaiian Volcano Observatory (USGS)

ICE - Instituto Costarricense de Electricidad (Costa Rica)

IG - Instituto Geofísico (Ecuador)

IGNS - Institute of Geological and Nuclear Sciences (New Zealand) - now GNS Science

INETER - Instituto Nicaragüense de Estudios Territoriales (Nicaragua)

INGEMMET - Instituto Geológical Minero y Metalúrgico (Peru)

INGEOMINAS - Instituto Colombiano de Geología y Minería (Colombia)

INGV-CT - Istituto Nazionale di Geofisica e Vulcanologia - Sezione di Catania (Italy)

INSIVUMEH - Instituto Nacional de Sismologia, Vulcanologia, Meteorologia e Hidrologia (Guatemala)

IRD - Institut de Recherche pour le Développement (France)

JMA - Japanese Meteorological Agency

KEMSD - Kamchatkan Experimental and Methodical Seismilogical Department

KVERT - Kamchatkan Volcanic Eruption Response Team

M - magnitude

METEOSAT - Meteorological Satellite

MEVO - Mount Erebus Volcano Observatory

MODIS - Moderate Resolution Imaging Spectroradiometer

MVO - Montserrat Volcano Observatory

MWO - Meteorological Watch Office

NEIC - National Earthquake Information Center

NIED - National Research Institute for Earth Science and Disaster Prevention (Japan)

NOAA - National Oceanic and Atmospheric Administration

NOTAM - Notice to Airmen

OVDAS - Observatorio Volcanologico de los Andes del Sur (Chile)

OFDA - Office of US Foreign Disaster Assistance

ONEMI - Oficina Nacional de Emergencia - Ministerio del Interior (Chile)

OVPDLF - Observatoire Volcanologique du Piton de la Fournaise (France)

OVSICORI-UNA - Observatorio Vulcanologico y Sismologico de Costa Rica, Universidad Nacional (Costa Rica)

PHIVOLCS - Philippine Institute of Volcanology and Seismology (Philippines)

RSAM - Real-time Seismic Amplitude Measurement

RVO - Rabaul Volcano Observatory

SERNAGEOMIN - Servicio Nacional de Geologia y Mineria (Chile)

SIGMET - Significant Meteorological Information

SNET - Servicio Nacional de Estudios Territoriales (El Salvador)

SVERT - Sakhalin Volcanic Eruption Response Team (Russia)

USAID - US Agency for International Development

USGS - United States Geological Survey

UTC - Coordinated Universal Time

VAAC - Volcanic Ash Advisory Center

VAFTAD - Volcanic Ash Forecast Transport And Dispersion

VDAP - Volcano Disaster Assistance Program (USGS)

VHP - Volcano Hazards Program (USGS)

VRC - Volcano Research Center (Japan)

Report for Bagana
Satellite imagery taken at 0551 on 13 May revealed a thin plume extending 28 km (15 nm) ESE below 3 km altitude (10,000 feet). Similar plumes, blowing W, were identified at 0537 on the 14th and at 0634 on 15 May.
Source: Darwin Volcanic Ash Advisory Centre (VAAC)
Report for Dieng Volcanic Complex
A pilot reported a plume from Dieng at 1029 on 13 May to about 3 km altitude (10,000 feet). Ash was not identified in satellite imagery a little more than an hour later.

[Following the original posting of this report, the Darwin VAAC provided the additional information that Indonesian aviation authorities and the Volcanological Survey of Indonesia (DVGHM) quickly confirmed on that day that the plume was not due to an eruption, but due to pipe maintenance at the geothermal energy site at Dieng. The original posting also incorrectly identified the Indonesian DVGHM as the source of the report, when it was actually a Volcanic Ash Advisory from the Darwin VAAC. The prompt follow-up by local authorities and correction of the original report is greatly appreciated.]
Source: Darwin Volcanic Ash Advisory Centre (VAAC)
Report for Fernandina
On 13 May the Charles Darwin Research Station (CDRS) received news that Fernandina, an island volcano in the Galapagos, had begun erupting that morning. Satellite photos showed a large cloud extending to the NW. On 14 May a joint Galápagos National Park and CDRS team flew over the eruption site. On approaching the island a large convection cloud could be seen rising above the main cloud layer above the volcano, but the caldera and rim could not be seen. On passing below the cloud, lava flows could be seen on the SW and S slopes. The first flow seems to have occurred more or less where the last eruption started in 1995, high on the SW slope, but from a circumferential fissure near the rim. The fissure itself could not be seen owing to the cloud on the rim, but map analysis suggests that the fissure was about 4.5 km long around the rim or just below it, with the first flows emanating from the W part of the fissure, and the latest flows from the E part. The flows descended the steepest part of the slopes quickly, and ponded on the gentler outer skirt of the island. The closest point that the lava had approached the sea on the 14th was 5.5 km from the coast. Lava passing through vegetated areas has caused small fires, but these have not spread far from the lava tongues themselves before going out. Most of the new flows have passed over unvegetated older lava.

A short time after the volcano started to erupt, the Sea-viewing Wide Field-of-view Sensor (SeaWiFS) flying on the OrbView-2 satellite captured an image showing a thick cloud of ash and steam fanning out W of the volcano, with a smaller, slightly darker plume blowing S. This darker plume may be more ash-rich than the larger plume, or it may be smoke from fires ignited by lava flows. Washington VAAC notices reported that the W-directed plume rose to about 5 km (17,000 feet) altitude on the afternoon of 13 May, and the S-directed plume went to 9 km (30,000 feet); both were visible later that day in satellite imagery more than 200 km from the volcano.

Thermal anomalies detected in MODIS satellite imagery, provided by the University of Hawaii, abundant on 14 and 15 May, were not evident on the 16th. Hot spots were again identified at the rim and down the S flank on 17 May.
Sources: Alan Tye, Charles Darwin Research Station, NASA Earth Observatory, Washington Volcanic Ash Advisory Center (VAAC), Hawai'i Institute of Geophysics and Planetology (HIGP) Thermal Alerts Team
Report for Anatahan
On 11 May the Air Force Weather Agency (AFWA) reported thick ash rising to 4.2 km altitude (14,000 feet) and moving WNW. The thick ash extended in a triangular shape from the summit 444 km (240 nm) to the WSW through 510 km (275 nm) to the NW. A layer of thin ash at 3 km altitude (10,000 feet) extended beyond the thick ash another 1,000 km (550 nm). A broad swath of VOG extended over 2,200 km (1,225 nm) W nearly to the Philippines and over 1400 km (775 nm) NNW of Anatahan. Although the ash plume diminished over the next few days and was not as thick, it remained significant, rising to 2.4 km (8,000 feet) and extending 370 km (200 nm) WNW on the 13th. Scientific personnel from EMO and the USGS repairing and installing equipment the next day reported hearing a continuous roaring sound from 2-3 km W of the active vent. They also saw ash and steam rising by pure convection, not explosively, to 3 km altitude (10,000 feet).
Source: Emergency Management Office of the Commonwealth of the Mariana Islands and United States Geological Survey Volcano Hazards Program
Report for Awu
At 1715 on 16 May a pilot reported a low-level plume above Awu. No ash was seen in satellite imagery about one hour or eight hours later.
Source: Darwin Volcanic Ash Advisory Centre (VAAC)
Report for Bezymianny
Weak gas-and-steam plumes were observed on 6-7 May, but clouds frequently obscure the volcano. A thermal anomaly at the dome was detected in satellite imagery on 6-8, 10, and 12 May. Bezymianny remained at Concern Color Code Yellow.
Source: Kamchatkan Volcanic Eruption Response Team (KVERT)
Report for Colima
Explosions during 11-17 May generated pyroclastic flows down all flanks of the volcano on at least three occasions. Incandescence was seen on a video camera late on 15 May, followed by an ash eruption that rose to 7.6 km altitude (25,000 feet) and moved E.
Sources: Centro Universitario de Estudios e Investigaciones de Vulcanologia - Universidad de Colima, Washington Volcanic Ash Advisory Center (VAAC)
Report for Fuego
Small white plumes to ~200 m height were again observed during 11-17 May. Lava flows down the Santa Teresa and Taniluya ravines reached 700 and 500 m long, respectively, with avalanches originating from their fronts.
Source: Instituto Nacional de Sismologia, Vulcanologia, Meteorologia, e Hidrologia (INSIVUMEH)
Report for Kanlaon
Multiple episodes of mild ash and steam ejections were observed at Canlaon during 10-11 May that sent clouds to heights of up to 500 m above the vent before being blown NW. These episodes were not seen in the seismic record. The hazard status remained at Alert Level 1.
Source: Philippine Institute of Volcanology and Seismology (PHIVOLCS)
Report for Karymsky
High seismic activity at Karymsky continued during 6-13 May. The number of local shallow events was 150-500 per day during the week. According to seismic data, possible ash-and-gas plumes rose up to the 1,000 m above the crater on 5, 8, and 9 May. According to satellite data, a thermal anomaly was registered on 6 and 8 May. Gas-and-steam plumes containing some ash extended ~40 km E on 6 May and ~30 km S on 9 May. Clouds obscured the volcano at other times. A larger eruption to 3 km altitude (10,000 feet) was reported on 18 May. Karymsky remained at Concern Color Code Orange.
Sources: Kamchatkan Volcanic Eruption Response Team (KVERT), Washington Volcanic Ash Advisory Center (VAAC)
Report for Kilauea
Ocean entries remained active during 11-17 May in the East Lae`apuki and Kamoamoa areas. By 16 May the East Lae`apuki and East Kamoamoa entries both had benches ~350 m long and up to 75 m wide. A large plume from West Highcastle on 10 May probably recorded a collapse of part of that lava delta, which has been inactive for the past several weeks following growth in March and April. The middle branch of the PKK flow remained active and extending down Pulama Pali. The east branch reached out farther but was narrower and contained fewer breakouts. The west branch was reduced to a cluster of breakouts about halfway down the pali. Glow was seen throughout the report period from all of the Pu`u `O`o crater vents, as well as the MLK vent at the SW foot of the cone. Background seismicity, both tremor and long-period earthquakes, remained above the norm at Kilauea's summit. Volcanic tremor is at a moderate level at Pu`u `O`o. Tilt at the summit was relatively flat, while Pu`u `O`o showed its usual ups and downs.
Source: US Geological Survey Hawaiian Volcano Observatory (HVO)
Report for Klyuchevskoy
Seismic activity was slightly above background levels until 7 May and at background levels on 8-9 May. Weak gas-and-steam plumes were seen rising up to 100 m above the crater and extended E on 6 May and for 5 km to the SE on 7 May. Clouds obscured the volcano at other times. A weak thermal anomaly was detected in satellite data during 6-9 May. Kliuchevskoi remained at Concern Color Code Yellow.
Source: Kamchatkan Volcanic Eruption Response Team (KVERT)
Report for Pacaya
Reports on 10 and 13 May indicated continued ejection of incandescent material from the crater. Lava flows moving towards the SW and W in the direction of Cerro Chino reached lengths of 150-250 m.
Source: Instituto Nacional de Sismologia, Vulcanologia, Meteorologia, e Hidrologia (INSIVUMEH)
Report for Santa Maria
Constant avalanches were reported on 10 May from the lava-flow front and the Caliente Dome, along with one small ash explosion. Minor explosions described in a 13 May report send gray ash plumes 400-600 m high. Avalanches from the SW-flank lava flow continued.
Source: Instituto Nacional de Sismologia, Vulcanologia, Meteorologia, e Hidrologia (INSIVUMEH)
Report for Sheveluch
Growth of the lava dome continued during 6-13 May. A gas-and-steam plume was seen rising up to 400 m above the dome on 6 May. Clouds obscured the volcano at other times. A large thermal anomaly at the dome was detected in satellite imagery all week. Shiveluch remained at Concern Color Code Orange.
Source: Kamchatkan Volcanic Eruption Response Team (KVERT)
Report for Soufriere Hills
The seismic network recorded 38 volcano-tectonic (VT) earthquakes, one hybrid earthquake and one rockfall during 6-13 May. Steam venting on the NW side of the crater continued. The daily recorded sulfur dioxide flux varied from a low of 221 metric tons per day (t/d) on 11 May to a maximum of 537 t/d on the 9th. The average of the six measurements during the week was 398 t/d, below the long-term eruption average of 500 t/d.
Source: Montserrat Volcano Observatory (MVO)
Report for Spurr
Elevated levels of seismicity continue to be recorded during 6-13 May. The AVO webcam images showed small steam plumes during the early part of this week. A pilot report received on 9 May described a small steam plume reaching 60-100 m (200-300 feet) above the summit crater. The crater lake level continues to drop, exposing more areas of steaming rock in the crater walls. Continued heat flux is indicated by vigorously upwelling water in the melt pit lake, rapid melting of ice and snow that has fallen into the lake, and minor steaming from rock surfaces and smaller melt pits in the vicinity of the summit crater. Spurr remained at Concern Color Code Yellow.
Source: US Geological Survey Alaska Volcano Observatory (AVO)
Report for St. Helens
Images from a camera at the mouth of the crater showed the new spine of lava at the N end of the dome continuing to grow during 11-12 May. Data from seismic and GPS instruments in the crater and on the outer flanks of the volcano show no significant changes from readings of the past few weeks. St. Helens remained at Volcano Advisory (Alert Level 2); aviation color code Orange.
Source: US Geological Survey Cascades Volcano Observatory (CVO)