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Smithsonian / USGS Weekly Volcanic Activity Report

You are currently viewing Archived reports for the week of 18 July-24 July 2001.


















 Activity for the week of 18 July-24 July 2001

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 at volcanoes that meet criteria discussed in detail in the "Criteria and Disclaimers" section. Carefully reviewed, detailed reports on various volcanoes are published monthly in the Bulletin of the Global Volcanism Network.

Name Location Activity
Etna Sicily (Italy) New
Sheveluch Central Kamchatka (Russia) New

Karangetang Siau Island (Indonesia) Ongoing
Kilauea Hawaiian Islands (USA) Ongoing
Krakatau Indonesia Ongoing
Mayon Luzon (Philippines) Ongoing
Merapi Central Java (Indonesia) Ongoing
Popocatepetl Mexico Ongoing
Semeru Eastern Java (Indonesia) Ongoing
Soufriere Hills Montserrat Ongoing
Tungurahua Ecuador Ongoing


New Activity / Unrest


Volcano index photo  Etna  | Sicily (Italy)  | 37.748°N, 14.999°E  | Elevation 3295 m

A large flank eruption began on 17 July at Etna and produced several lava flows that were emitted from four new fissures and strong explosive activity at a fifth. Four of the fissures were on the SE flank, and the fifth was on the NE flank. There were fears that lava flows from two of the fissures would reach the town of Nicolosi (~15 km SSE of the volcano) and a nearby popular tourist area. According to the Italy's Volcanoes website, the 17th eruptive episode in 2001 began on the morning of 17 July and a few hours later a new eruptive fissure opened at the S base of the Southeast Crater cone (see map of fissure locations). Mild Strombolian activity occurred from the fissure and a lava flow extended SSE. During the evening of the 17th a second eruptive fissure emitted an extensive lava flow that spread SE toward the Valle del Bove rim. On 18 July at about 0200 a seismic swarm was accompanied by the opening of a third eruptive fissure at about 2,100 m elevation. Mild Strombolian activity and a sluggish lava flow traveled toward the S. Later in the day the lava flow crossed the main access road to the S flank of Etna and headed towards Nicolosi. A spectator was seriously injured when he fell while trying to avoid projectiles.

On the evening of 18 July the fourth eruptive vent since the episode began opened near 2,700 m elevation on the SE flank. The main explosive activity occurred at this vent, including powerful Strombolian blasts that sent incandescent volcanic bombs as high as 200 m and produced ash columns that rose several kilometers. Lava from this vent progressed towards the tourist complex around the Rifugio Sapienza. On 20 July around 1100 a fifth eruptive fissure became active, but unlike the other fissures it was on the NE flank in the Valle de Leone. Lava emitted from this fissure flowed SE.

By 22 July the lava flow from the third fissure was 4 km away from Nicolosi, but it was advancing very slowly over nearly flat terrain and appeared to have stopped by the next day. Earth barriers were created in an attempt to divert lava from the tourist complex that had already been damaged by volcanic bombs. Continuous ashfall occurred near the explosive fourth vent. The entire area between the towns of Giarre (~17 km E of the volcano) and Catania (~25 km SSE of the volcano) was covered by a thin layer of ash; there was an especially large amount of ash in Catania. The Fontanarossa International Airport of Catania was closed on 22 July and again the next day due to ashfall.

The Toulouse VAAC reported that the new Etna Sistema Poseidon webcam showed ash emission starting on 20 July. The previous webcam had been damaged by earthquakes near the start of the eruption. SE-drifting ash clouds were detected several times on satellite imagery. An ash cloud was reported to have reached a maximum height of ~5.2 km on 22 July. According to news reports, a state of emergency was declared for the area near Etna on 20 July. As of 24 July the eruption was continuing.

Sources: Italy's Volcanoes, Etna Volcan Sicilien (Charles Rivière), Toulouse Volcanic Ash Advisory Centre (VAAC), NASA Earth Observatory, Reuters



Volcano index photo  Sheveluch  | Central Kamchatka (Russia)  | 56.653°N, 161.36°E  | Elevation 3283 m

A moderate-sized eruption at Shiveluch on 19 July prompted KVERT to raise the Concern Color Code from Yellow to Orange the same day. The eruption occurred at 1033 and produced an ash plume that rose 3 km above the lava dome. Prior to the eruption, during 14 through 16 July, spasmodic volcanic tremor increased several times. On 15 July at 1803 a three-pixel thermal anomaly was visible on AVHRR satellite imagery near the SW flank of the volcano. Also, at 2100 a gas-and-steam plume was observed rising 1.5 km above the dome.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)



Ongoing Activity


Volcano index photo  Karangetang  | Siau Island (Indonesia)  | 2.781°N, 125.407°E  | Elevation 1797 m

During 9-15 July volcanic activity was at a level similar to the previous week. Seismicity was dominated by 572 small explosions, 451 multiphase earthquakes, and continuous lava avalanches. The avalanches traveled up to 2.5 km down the Keting River and lava flowed as far as 750 m down the Kahetang River. In addition, a gray plume was emitted from the volcano, which remained at Alert Level 3 (on a scale of 1-4).

Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM)



Volcano index photo  Kilauea  | Hawaiian Islands (USA)  | 19.421°N, 155.287°W  | Elevation 1222 m

During the week lava entered the sea at a moderate rate at the E Kupapa`u entry. On 18 July at 1803 a M 3.5 earthquake rattled though the lower east rift zone of Kilauea. Surface flows were vigorous in two areas of the current lava flow field; one in the E branch of the flow field at the base of the Pulama pali scarp, and the other just SE of the shatter ring in the W branch of the flow field. Generally, weak, steady tremor and a few related long-period earthquakes continued beneath Kilauea's caldera. Near Pu`u `O`o, the tremor alternated from weak, to moderate, to strong over periods of several hours. Elsewhere, seismicity was at normal levels. Tiltmeters in the summit area and along the east rift zone indicated no significant deformation.

Source: US Geological Survey Hawaiian Volcano Observatory (HVO)



Volcano index photo  Krakatau  | Indonesia  | 6.102°S, 105.423°E  | Elevation 155 m

There were 728 shallow volcanic earthquakes at Krakatau during 9-15 July, which was a significant increase in comparison to the previous week. No visual observations were made. The volcano remained at Alert Level 2 (on a scale of 1-4).

Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM)



Volcano index photo  Mayon  | Luzon (Philippines)  | 13.257°N, 123.685°E  | Elevation 2462 m

Volcanic activity at Mayon was similar to the previous week. During 17-23 July seismicity consisted of four high-frequency and 37 low-frequency earthquakes, and 203 high-frequency short-duration harmonic tremors. An average of 4,100 metric tons per day of SO2 was emitted from the volcano, which was still above the baseline value of 500 metric tons per day. There was an overall deflationary trend and the intensity of incandescence observed at the crater ranged from barely visible to bright. Rockfalls occasionally rolled from the crater SE towards the Bonga Gully. The volcano remained at Alert Level 3 (on a scale of 0-5).

Source: Philippine Institute of Volcanology and Seismology (PHIVOLCS)



Volcano index photo  Merapi  | Central Java (Indonesia)  | 7.54°S, 110.446°E  | Elevation 2910 m

During 9-15 July volcanic activity at Merapi was similar to the previous week. A total of 52 lava avalanches traveled SW to a maximum distance of 2.5 km down the Sat, Senowo, and Lamat rivers. Emissions from low-pressure fumaroles rose to 755 m above the summit. The volcano remained at Alert Level 2 (on a scale of 1-4).

Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM)



Volcano index photo  Popocatepetl  | Mexico  | 19.023°N, 98.622°W  | Elevation 5393 m

Several small-to-moderate sized emissions occurred at Popocatépetl that were mainly composed of steam, gas, and small amounts of ash.

Source: Centro Nacional de Prevencion de Desastres (CENAPRED)



Volcano index photo  Semeru  | Eastern Java (Indonesia)  | 8.108°S, 112.922°E  | Elevation 3657 m

Seismic data revealed that during 9-15 July activity was higher than in the previous week. During this period 687 explosion events were recorded, as well as 57 avalanches, and 11 tectonic earthquakes. The volcano remained at Alert Level 2 (on a scale of 1-4).

Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM)



Volcano index photo  Soufriere Hills  | Montserrat  | 16.72°N, 62.18°W  | Elevation 915 m

The number of rockfalls increased (719) during 13-20 July in comparison to the previous week (297), although most of them were very small. Near-continuous rockfalls occurred on the S side of the lava dome, where dome growth was concentrated. Numerous pyroclastic flows originated from the S flank of the dome and moved eastward down the Tar River Valley. Several pyroclastic flows also originated from the W side of the dome and traveled short distances into the upper part of the Gages area. On 23 July at 1145 a pilot reported spotting an ash cloud approximately 800 m above the volcano. Satellite imagery at that time detected a faint ash-and-steam plume and an occasional hot spot.

Sources: Montserrat Volcano Observatory (MVO), Washington Volcanic Ash Advisory Center (VAAC)



Volcano index photo  Tungurahua  | Ecuador  | 1.467°S, 78.442°W  | Elevation 5023 m

During the week heavy rain remobilized ash deposited on the flanks of the volcano, generating lahars, and several small-to-moderate eruptions produced ash clouds. On 19 July lahars that traveled down the W flank of the volcano reached the Baños-Riobamba highway. The Washington VAAC reported that one of the larger eruptions during the week occurred on 20 July at 2104 and produced an ash cloud that rose to ~7.9 km a.s.l.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)



Weekly Reports Archive

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Bamus Huila, Nevado del Momotombo Sotara
Banda Api Hunga Tonga-Hunga Ha'apai Monowai Soufriere Hills
Bardarbunga Ibu Montagu Island Soufriere St. Vincent
Barren Island Ijen Moyorodake [Medvezhia] South Sarigan Seamount
Batur Iliamna Mutnovsky Spurr
Bezymianny Iliwerung Myojinsho St. Helens
Bogoslof Inielika Nabro Stromboli
Brava Ioto Negra, Sierra Sulu Range
Bristol Island Iya Negro, Cerro Sumbing
Bulusan Izu-Torishima Nightingale Island Sundoro
Calbuco Jackson Segment Nishinoshima Suretamatai
Callaqui Kaba Nisyros Suwanosejima
Cameroon Kadovar Novarupta Taal
Campi Flegrei del Mar di Sicilia Kambalny NW Rota-1 Tair, Jebel at
Cayambe Kanaga Nyamuragira Takawangha
Cereme Kanlaon Nyiragongo Talang
Chachadake [Tiatia] Karangetang Okataina Tambora
Chaiten Karkar Okmok Tanaga
Chiginagak Karthala Ontakesan Tandikat-Singgalang
Chikurachki Karymsky Oraefajokull Tangkoko-Duasudara
Chiles-Cerro Negro Kasatochi Osorno Tangkuban Parahu
Chillan, Nevados de Katla Pacaya Tara, Batu
Chirinkotan Kavachi Pagan Telica
Chirpoi Kelimutu Paluweh Tenerife
Cleveland Kelut Panarea Tengger Caldera
Colima Kerinci Papandayan Three Sisters
Colo Ketoi Parker Tinakula
Concepcion Kharimkotan Pavlof Tofua
Copahue Kick 'em Jenny Peuet Sague Tokachidake
Cotopaxi Kikai Pinatubo Tolbachik
Cuicocha Kilauea Planchon-Peteroa Toliman
Cumbal Kirishimayama Poas Tongariro
Dabbahu Kizimen Popocatepetl Tungurahua
Dempo Klyuchevskoy Puyehue-Cordon Caulle Turrialba
Descabezado Grande Kolokol Group Rabaul Ubinas
Dieng Volcanic Complex Korovin Raikoke Ulawun
Dukono Koryaksky Ranakah Unknown Source
Ebeko Krakatau Raoul Island Unnamed
Ebulobo Krummel-Garbuna-Welcker Rasshua Unnamed
Egon Kuchinoerabujima Raung Veniaminof
Ekarma Kurikomayama Redoubt Villarrica
Epi Kusatsu-Shiranesan Reventador West Mata
Erebus Kverkfjoll Reykjanes White Island
Erta Ale Lamington Rincon de la Vieja Witori
Etna Lamongan Rinjani Wolf
Etorofu-Yakeyama [Grozny Group] Langila Ritter Island Yasur
Eyjafjallajokull Lanin Rotorua Zaozan [Zaosan]
Fernandina Lascar Ruang Zavodovski
Fogo Lateiki Ruapehu Zhupanovsky
Fonualei Lengai, Ol Doinyo Ruiz, Nevado del Zubair Group
Fournaise, Piton de la Leroboleng Sabancaya
Fourpeaked Lewotobi Sakar
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 News Feeds and Google Placemarks


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. 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.




The CAP (Common Alerting Protocol) feeds are XML files specifically formatted for disaster management. They are similar in content to the RSS feed, but contain no active links.




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 page for that volcano and to the complete Weekly Report for that week.

 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.

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URL https://volcano.si.edu/reports_weekly.cfm
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RSS and CAP Feeds

An RSS (Really Simple Syndication) feed for the Weekly Volcanic Activity Report first made available on 5 March 2008 can be utilized with the aid of various free downloadable readers. The report content of the news 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. 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. On 12 March 2009, GeoRSS tags were added so that the latitude and longitude for each volcano could be included with the feed.

At the end of each individual report is a list of the sources used. We would like to emphasize that the World Organization of Volcano Observatories (WOVO) website (http://www.wovo.org/) lists the regional volcano observatories that have the most authoritative data for many of these events.

CAP (Common Alerting Protocol) feeds are XML files specifically formatted for disaster management.


Google Earth Placemarks

A Google Earth network link for the Weekly Volcanic Activity Report was first made available on 1 April 2009. This file 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 page for that volcano and to the complete Weekly Report for that week.

 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)