Activity for the week of 30 November-6 December 2011
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.
New Activity / Unrest
| 14.473°N, 90.88°W
| Elevation 3763 m
INSIVUMEH reported that on 1 December explosions from Fuego produced ash plumes that rose 800 m above the crater and drifted to the S. Avalanches descended toward Ash Creek. During 5-6 December ash plumes rose to an altitudes of 400-500 m above the crater and drifted to the W. A 150-m-long lava flow descended toward Ash Creek and avalanches reached vegetated areas.
Based on information from INSIVUMEH, the Washington VAAC reported gas and ash emissions on 2 December and a possible ash plume rose to an altitude of km (10,000 ft) a.s.l. on 6 December.
Sources: Instituto Nacional de Sismologia, Vulcanologia, Meteorologia, e Hidrologia (INSIVUMEH), Washington Volcanic Ash Advisory Center (VAAC)
| 1.22°N, 77.37°W
| Elevation 4276 m
INGEOMINAS reported that observations of Galeras during an overflight on 29 November revealed thermal analomies in the main crater. During an overflight on 6 December scientists observed that gas emissions rose from the main crater and two craters to the N and SW (Paisita and Chavas, respectively) and had increased in comparison to the previous week. Thermal anomalies were also detected in the main crater. INGEOMINAS raised the Alert Level to III (Yellow; "changes in the behavior of volcanic activity") on 6 December.
Source: Servicio Geológico Colombiano (SGC)
| Halmahera (Indonesia)
| 0.8°N, 127.33°E
| Elevation 1715 m
CVGHM raised the Alert Level for Gamalama from 2 to 3 (on a scale of 1-4) on 4 December based on seismicity and visual observations during 1-4 December. On 1 and 4 December white plumes rose to an altitude of 0.15 km (492 ft) a.s.l. and drifted W. Clouds obscured views on the other days.
Based on information from CVGHM, the Darwin VAAC reported that during 5-6 December ash plumes from Gamalama rose to altitudes of 2.4-3.0 km (8,000-10,000 ft) a.s.l. and drifted SE.
Sources: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM), Washington Volcanic Ash Advisory Center (VAAC)
| Mariana Islands (USA)
| 18.13°N, 145.8°E
| Elevation 570 m
A Northern Mariana Islands status report noted that clear to partly-cloudy satellite images showed a persistent gas-and-steam plume drifting from Pagan during 25 November-2 December. The Aviation Color Code remained at Yellow and the Volcano Alert Level remained at Advisory.
Source: Emergency Management Office of the Commonwealth of the Mariana Islands and United States Geological Survey Volcano Hazards Program
| 1.467°S, 78.442°W
| Elevation 5023 m
IG reported that seismicity has remained the same from the previous week from Tungurahua, but the number of explosions has increased during 30 November-6 December. Incandescent blocks traveled 1 km down the flanks, and roaring noises and sounds resembling "cannon shots" were reported all week. Ashfall was reported from almost all populations near the volcano during the week. Ash plumes rose to altitudes of 1.5-5.0 km (4,920-16,400 ft) and drifted in multiple directions. On the night of 2 December lahars descended into the drainages and ejected incandescent blocks 500 m above the crater.
Seismicity increased on 3 December. During 3-5 December pyroclastic flows descended on the W flanks. Pyroclastic flows were also reported on the NW flank on 4 December, and large explosions occurred at 0130, 0600, and 1330. Significant ashfall was reported in San Juan, Manzano (8 km SW), and Bilbao (8 km W). On 5 December incandescent blocks were ejected 300 m above the crater and gray ash was deposited mainly to the E. On 6 December incandescence and Strombolian activity was observed.
Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)
| Kyushu (Japan)
| 31.593°N, 130.657°E
| Elevation 1117 m
Based on information from JMA, the Tokyo VAAC reported that during 30 November and 2-6 December explosions from Sakura-jima produced plumes that rose to altitudes of 1.2-3.0 km (4,000-10,000 ft) a.s.l. and drifted NE, E, SE, W, NW. Satellite imagery and a pilot report on 30 November showed an ash plume at an altitude 3.7 km (12,000 ft) a.s.l and drifted 37 km SE. On 5 December a pilot report and satellite imagery showed an ash plume at an altitude of 3.7 km (12,000 ft) a.s.l and drifted 74 km S.
Source: Tokyo Volcanic Ash Advisory Center (VAAC)
| Halmahera (Indonesia)
| 1.693°N, 127.894°E
| Elevation 1229 m
Based on analyses of satellite imagery, the Darwin VAAC reported that on 29 November ash plumes from Dukono rose to an altitude of 2.1 km (7,000 ft) a.s.l. and drifted 65 km NW.
Source: Darwin Volcanic Ash Advisory Centre (VAAC)
| 27.73°N, 18.03°W
| Elevation 1500 m
Instituto Geográfico Nacional (IGN) reported that during 30 November-6 December the submarine eruption continued S of El Hierro Island, with lava balloons sporadically observed floating on the sea. During this period, the mean tremor amplitude was similar to the previous week. Twenty-eight seismic events were located, most of them offshore to the N of the island at depths of 15-24 km and with a maximum magnitude of 2.8. Only one of these events was felt by residents at a maximum intensity value of II using EMS-98 (European Macroseismic Scale). GPS data analyses showed stability in the horizontal components; the vertical component at stations located on the S and NE parts of the island showed subsidence.
Source: Instituto Geográfico Nacional (IGN)
| Eastern Kamchatka (Russia)
| 54.049°N, 159.443°E
| Elevation 1513 m
KVERT reported that seismic activity continued at a moderate level at Karymsky during 25 November-2 December and indicated that possible ash plumes rose to an altitude of 3.8 km (12,500 ft) a.s.l. during the week. Satellite imagery showed a thermal anomaly on the volcano during 28-30 November and 1 December. The Aviation Color Code remained at Orange.
Source: Kamchatkan Volcanic Eruption Response Team (KVERT)
| Hawaiian Islands (USA)
| 19.421°N, 155.287°W
| Elevation 1222 m
During 30 November-6 December, HVO reported that the lava lake circulated and periodically rose and fell in the deep pit within Kilauea's Halema'uma'u Crater, remaining below the inner ledge (75 m below the crater floor). Almost daily measurements indicated that the gas plume from the vent continued to deposit variable amounts of ash and fresh spatter nearby. Incandescence was visible from the E and W edges of the Pu'u 'O'o crater floor, and from the 21 September fissure on the SE flank of Pu'u 'O'o cone.
On 2 December incandescence was seen from a new area low on the N flank of Pu'u'O'o. Pahoehoe flows, fed through lava tubes from the fissure, continued to be active about 6.8 km SE of Pu'u 'O'o based on intermittent views from satellite, ground observers and an overflight on 3 December. During 4-5 December the vent on the E edge of the crater produced lava flows that partially filled the depression left by the flank fissure eruption in September and a perched lava lake was built on 6 December.
Source: US Geological Survey Hawaiian Volcano Observatory (HVO)
| Eastern Kamchatka (Russia)
| 55.131°N, 160.32°E
| Elevation 2334 m
KVERT reported a decrease in seismic activity at Kizimen during 25 November-2 December and a thermal anomaly that was detected daily in satellite images. A large lava flow on the NE and E flanks continued to effuse. The video camera was down due to technical reasons during the week. Pilot reports indicated gas-and-steam activity during 27-28 November and plumes rose to an altitude of 5 km (16,400 ft) a.s.l. The Aviation Color Code remained at Orange.
Source: Kamchatkan Volcanic Eruption Response Team (KVERT)
| 19.023°N, 98.622°W
| Elevation 5393 m
CENAPRED reported that during 30 November-6 December steam-and-gas emissions rose from Popocatépetl and crater incandescence was observed during most nights and early mornings. Steam-and-gas emissions occasionally contained small amounts of ash on 30 November and 5 December.
Based on information from the Mexico City MWO, the Washington VAAC reported that an ash plume rose to an altitude of 6.7 km (22,000 ft) a.s.l. and drifted NE on 5 December. That same day satellite imagery showed the ash plume had dissipated.
Sources: Centro Nacional de Prevencion de Desastres (CENAPRED), Washington Volcanic Ash Advisory Center (VAAC)
| 40.59°S, 72.117°W
| Elevation 2236 m
Based on seismicity during 30 November-6 December, OVDAS-SERNAGEOMIN reported that the eruption from the Cordón Caulle rift zone, part of the Puyehue-Cordón Caulle volcanic complex, continued at a low level. During 1-3 and 5 December plumes observed with the web camera rose 1.5-3 km above the crater. On 1 December satellite imagery showed an ash plume drifting 90 km SSE with sparse ashfall to the W and NW and dissipated 100 km to the SE. During the night the crater was incandescent. Satellite imagery showed an ash plume drifting E and SE and reaching the Atlantic Ocean on 2 December. Cloud cover prevented satellite data during 3-4 December. On 5 December satellite imagery showed a plume drifting 100 km NW. The Alert Level remained at Red.
Source: Servicio Nacional de Geología y Minería (SERNAGEOMIN)
| Central Kamchatka (Russia)
| 56.653°N, 161.36°E
| Elevation 3283 m
KVERT reported that moderate seismic activity was detected at Shiveluch during 25 November-2 December, and satellite imagery showed a daily thermal anomaly over the lava dome. Ground-based observers noted that a viscous lava flow continued to effuse in the crater formed during a 2010 eruption. A gas-and-steam plume detected in satellite imagery drifted 22 km NW on 26 November. Moderate fumarolic activity at the lava dome was observed during 28-29 November; clouds prevented observations on the other days of the week. The Aviation Color Code remained at Orange.
Source: Kamchatkan Volcanic Eruption Response Team (KVERT)
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 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
Contact: USGS Web Team
USGS Privacy Statement
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.