All times are local unless otherwise stated.

Hood | 12 September-18 September 2001 | New Activity / UnrestCite this Report
Hood Oregon	The USGS Cascades Volcano Observatory reported that a minor earthquake swarm occurred at Mount Hood from 9 September until at least 14 September. About 25 events were detected, with a maximum magnitude of 2.9. The epicenters of the earthquakes were ~8 km SSW of the volcano's summit at depths of 1-7 km. These types of swarms occur once or twice per year at Mount Hood. Source: US Geological Survey Cascades Volcano Observatory (CVO)
Kama'ehuakanaloa | 12 September-18 September 2001 | New Activity / UnrestCite this Report
Kama'ehuakanaloa Hawaiian Islands (USA)	An earthquake swarm occurred at Loihi during 10-11 September and two 13 September earthquakes may have also been part of the swarm. The two later earthquakes occurred at 0311 and 0839 and had magnitudes of 4.9 and 4.4, respectively. Most of the earthquakes from 10-13 September were ~12 km deep and located slightly S of the summit of the volcano. Source: US Geological Survey Hawaiian Volcano Observatory (HVO)

Etna | 12 September-18 September 2001 | Continuing ActivityCite this Report
Etna Sicily (Italy)	Volcanic activity resumed at Etna's summit on 11 September. Loud explosions emanated from the NW vent of Bocca Nuova crater at 5- to 10-minute intervals. The explosions were followed by dense gas clouds, but no volcanic fragments were ejected. Source: Italy's Volcanoes
Karangetang | 12 September-18 September 2001 | Continuing ActivityCite this Report
Karangetang Sangihe Islands	During 3-9 September lava flowed 0.5-1.8 km towards the Kahetang and Keting rivers. Lava avalanches that originated from the edges of the flows traveled up to 1 km. On 9 September at 0001 a pyroclastic flow traveled as far as 750 m from the main crater to the Batang River (West Siau). During the week seismicity was dominated by small explosion, avalanche, and multiphase earthquakes. Discontinuous volcanic tremor was also detected. The volcano remained at Alert Level 3 (on a scale of 1-4). Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM)
Kerinci | 12 September-18 September 2001 | Continuing ActivityCite this Report
Kerinci Central Sumatra	During 3-9 September activity at Kerinci was dominated by 1,128 small explosion earthquakes. On 9 September during 0800-1200 small explosions produced ash plumes that rose to 0.5 km above the volcano. Kerinci remained at Alert Level 2 (on a scale of 1-4). Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM)
Kilauea | 12 September-18 September 2001 | Continuing ActivityCite this Report
Kilauea Hawaiian Islands (USA)	Lava continued to flow down the Paluma pali scarp, across the coastal flat, and into the ocean at the E Kupapa`u ocean entry. Generally, volcanic tremor remained at low-to-moderate levels at Kilauea's summit and Pu`u `O`o. During 12 and 13 September very slight deflation occurred at Kiliauea's summit. During the rest of the week tiltmeters across the volcano showed no significant deformation. On 17 September at Pu`u `O`o, background tremor was interrupted at intervals of ten's of minutes to an hour or two, by short-lived bursts of relatively vigorous tremor. Source: US Geological Survey Hawaiian Volcano Observatory (HVO)
Krakatau | 12 September-18 September 2001 | Continuing ActivityCite this Report
Krakatau Sunda Strait	In comparison to the previous week there was a significant increase in explosion and volcanic earthquakes at Krakatau during 3-9 September. The number of small explosion earthquakes sharply decreased. 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)
Popocatepetl | 12 September-18 September 2001 | Continuing ActivityCite this Report
Popocatepetl Mexico	During the week, volcanic activity at Popocatépetl consisted of small emissions of steam, gas, and minor amounts of ash. Source: Centro Nacional de Prevencion de Desastres (CENAPRED)
Sheveluch | 12 September-18 September 2001 | Continuing ActivityCite this Report
Sheveluch Central Kamchatka (Russia)	During 7-14 September several gas-and-ash plumes produced from explosions at Shiveluch were observed, with the highest rising 1.2 km above the dome. On 11 September several hot avalanches were observed travelling from the top of the lava dome. On 12 September explosions produced a short pyroclastic flow and an ash plume that rose to 1 km above the dome. During the week, seismic activity was above background levels and spasmodic volcanic tremor and weak, shallow seismic signals (possible collapses and avalanches) were registered. Thermal anomalies were visible on satellite imagery. The volcano remained at Concern Color Code Orange. Source: Kamchatkan Volcanic Eruption Response Team (KVERT)
Soufriere Hills | 12 September-18 September 2001 | Continuing ActivityCite this Report
Soufriere Hills Montserrat	Activity at Soufrière Hills remained at levels similar to the previous week. Bands of tremor, associated with rockfalls and ash venting, occurred at irregular intervals. On 12 September continuous low-amplitude tremor began and persisted until at least 14 September. The tremor accompanied rockfalls. The active lava dome continued to produce rockfalls and small pyroclastic flows that descended into the upper reaches of the Tar River Valley. Ash clouds produced from rockfalls rose slightly above the summit and were visible in satellite imagery. Sources: Washington Volcanic Ash Advisory Center (VAAC), Montserrat Volcano Observatory (MVO)
Tungurahua | 12 September-18 September 2001 | Continuing ActivityCite this Report
Tungurahua Ecuador	During the week volcanic activity at Tungurahua was characterized by a large number of long-period earthquakes, near-summit ash-and-gas emissions, and sporadic small-to-moderate explosions. The highest ash cloud reached ~8 km a.s.l. On 11 September, and to a lesser extent on 12 September, ash fell to the N of the volcano in the towns of Pondoa, Runtun, and Baños. In addition, ash fell to the SW in Quero and Penipe, and mud flows were reported in Penipe. Explosions on 13 September deposited ash to the W of the volcano, affecting the towns of Juive, Cotalo, and Bibao. On the 15th ash fell to the SW in Riobamba and Penipe. On 16 September incandescent material was emitted from the volcano along with ash and gas. The Alert Level remained at Yellow in the town of Baños and at Orange for the rest of the population in the high-risk zone, as it has since 5 September 2000. Sources: Washington Volcanic Ash Advisory Center (VAAC), Instituto Geofísico-Escuela Politécnica Nacional (IG)

Weekly Reports Archive

Since the Weekly Volcanic Activity Report began in November 2000, there have been 18,613 individual reports over 1,152 weeks (average of 16 per week) on 329 different volcanoes.

Use the dropdowns to choose the year and week for archived Weekly Reports.

 News Feeds and Google Placemarks

 Criteria & Disclaimers

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.

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 cover longer time periods and are 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)