Activity for the week of 16 February-22 February 2005
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.
| Mariana Islands (USA)
| 16.35°N, 145.67°E
| Elevation 790 m
Eruptive activity at Anatahan declined steadily during the week of 14 February to a level that was less than 5% of the peak level attained during the eruption that began on 5 January. Ash eruptions continued, and the 2003 crater floor was almost entirely covered by fresh lava to a diameter of about one kilometer. On 21 February, seismic and acoustic records from Anatahan showed very low levels of activity over the previous 5 days. A MODIS image taken at 0115 on 18 February showed a plume of steam and vog (fog composed of volcanic fumes) extending about ~170 km SW of Anatahan.
Source: Emergency Management Office of the Commonwealth of the Mariana Islands and United States Geological Survey Volcano Hazards Program
| 19.514°N, 103.62°W
| Elevation 3850 m
During 16-21 February, several small explosions at Colima produced ash plumes that rose to low levels; plumes drifted predominately SE and W.
Source: Centro Universitario de Estudios e Investigaciones de Vulcanologia - Universidad de Colima
| Flores Island (Indonesia)
| 8.676°S, 122.455°E
| Elevation 1661 m
According to a news report, as of 17 February recent eruptive activity at Egon had prompted the local government to evacuate hundreds of residents living near the volcano.
Source: The Jakarta Post
| Siau Island (Indonesia)
| 2.781°N, 125.407°E
| Elevation 1797 m
DVGHM reported that on 16 February, a lava flow traveled 600 m from Karangetang's crater towards Kali Nanitu. Lava avalanches in the same area traveled as far as 1,200 m down the volcano's flank. At 1830 that day a pyroclastic flow traveled ~3,400 m, reaching the sea. Karangetang remained at Alert Level 3 (on a scale of 1-4).
Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM)
| Hawaiian Islands (USA)
| 19.421°N, 155.287°W
| Elevation 1222 m
On 21 February a new ocean entry, named East Lae`apuki, started at Kilauea. The entry was located between the other two ocean entries (Ka`ili`ili and West Highcastle) that had been active since 31 January 2005. This was the first time there had been three ocean entries active since early 2003. During 17-22 February, surface lava flows were visible on the volcano. A few small earthquakes occurred at Kilauea's summit, and no tremor was recorded. Tremor was at moderate levels at Pu`u `O`o. Small amounts of deformation occurred during the report period.
Source: US Geological Survey Hawaiian Volcano Observatory (HVO)
| Central Kamchatka (Russia)
| 56.056°N, 160.642°E
| Elevation 4754 m
During 11-18 February, seismicity was above background levels at Kliuchevskoi, with a large number of shallow earthquakes occurring daily. Ash plumes rose ~3 km above the volcano's crater during 12-14 February. Phreatic bursts, which occurred when lava flows contacted a glacier, were seen on 12 and 13 February. During 12-16 February, volcanic bombs were hurled 300-500 m above the crater, Strombolian activity occurred in the crater, and lava traveled into Krestovsky channel on the volcano's NW flank. During a flight on 16 February, a mudflow was seen extending 27 km. According to a news report, a lava flow from Kliuchevskoi melted a large section of Ehrman glacier. Kliuchevskoi remained at Concern Color Code Orange.
Source: Kamchatkan Volcanic Eruption Response Team (KVERT)
| Papua New Guinea
| 4.08°S, 145.037°E
| Elevation 1807 m
According to RVO, mild eruptive activity was observed from Manam's Southern Crater during 18-21 February. Weak-to-moderate ash explosions the crater emitted rose a few hundred meters above the crater and drifted E and SE, depositing fine ash in areas downwind. Main Crater emitted white vapor. Seismicity was at low levels at Manam, with small low-frequency earthquakes occurring. Manam remained at Alert Level 2.
Source: Rabaul Volcano Observatory (RVO)
Piton de la Fournaise
| Reunion Island (France)
| 21.244°S, 55.708°E
| Elevation 2632 m
A new period of heightened seismic activity began at Piton de la Fournaise on 17 February around 1300, consisting of about 100 seismic events within 90 minutes. After that, the number of events decreased, but recommenced at 1638 with several hundreds of events. Strong deformation was recorded at the same time by tiltmeters and the extensometer network. Eruption tremor began around 2035, becoming strong at 2050. The eruption site seemed to be situated close to Nez Coupé de Sainte Rose (on the N side of the volcano), and lava flows were observed in the Grand Brûlé area. According to a news report, the eruption ended on 19 February.
Sources: European Volcanological Society (SVE), Observatoire Volcanologique du Piton de la Fournaise (OVPF)
| New Britain (Papua New Guinea)
| 4.271°S, 152.203°E
| Elevation 688 m
During 1-21 February, eruptions of ash clouds occurred fairly frequently at Rabaul caldera's Tavurvur cone. Ash clouds rose a few hundred meters, drifted SE, and deposited ash mainly offshore. Incandescent lava fragments were visible during several evenings. Between 200-350 earthquakes associated with the eruption occurred daily. During 18-21 February, ash fell in the town of Tokua.
Source: Rabaul Volcano Observatory (RVO)
| Central Kamchatka (Russia)
| 56.653°N, 161.36°E
| Elevation 3283 m
Seismicity was above background levels at Shiveluch during 11-18 February, with weak shallow earthquakes occurring beneath the active lava dome. Ash plumes may have risen to a maximum height of 7.4 km a.s.l. on 17 February. Possible weak ash-and-gas explosions and hot avalanches occurred during the week. Ash deposits were seen on the volcano's snow-covered lava dome extending to the SE and S. Shiveluch remained at Concern Color Code Orange.
Source: Kamchatkan Volcanic Eruption Response Team (KVERT)
| United States
| 46.2°N, 122.18°W
| Elevation 2549 m
During 16-22 February, growth of the new lava dome inside the crater of St. Helens continued, accompanied by low rates of seismicity, low emissions of steam and volcanic gases, and minor production of ash. A GPS unit deployed on 16 February on the E arm of the glacier within the volcano's crater moved northward about 1.2 m per day. This rapid rate of flow was consistent with the thickening of the glacier that resulted from its compression between the growing lava dome and E crater wall. A thermal imaging flight on the 16th suggested that a longitudinal crack was developing along the top of the new lava dome.
On the afternoon of 18 February, a rockfall off of the lava dome produced an ash plume that rose several hundred meters above the crater rim. CVO reported that extensive cracking on the long, smooth, whaleback-shaped lava dome suggested that increased rockfall activity and similar small plumes could occur in the coming weeks. Analysis of recent airphotos showed that as of 1 February the high point on the whaleback-shaped extrusion was 2,330 m (nearly 425 m above the 1980 crater floor and 150 m above the top of the old lava dome). The extrusion was about 470 m long, and 150 m wide. The new lava dome, uplifted area of crater floor, and deformed glacier ice grew to a combined volume of about 38 million cubic meters, almost one-half the volume of the old lava dome. St Helens remained at Volcano Advisory (Alert Level 2); aviation code Orange.
Source: US Geological Survey Cascades Volcano Observatory (CVO)
| 1.467°S, 78.442°W
| Elevation 5023 m
Volcanic and seismic activity were at low levels at Tungurahua during 16-22 February. Low-energy gas, steam, and ash plumes were emitted. In addition, long-period earthquakes and episodes of tremor were recorded.
Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)
| United States
| 56.17°N, 159.38°W
| Elevation 2507 m
During 11-18 February, it was likely that low-level Strombolian eruptive activity continued at Veniaminof based on seismic data and satellite imagery. Cloudy conditions obscured web camera views of the volcano, and no ash emissions were observed above the cloud cover. Seismicity remained above background levels at Veniaminof. The character of the seismicity changed slightly during the report period, with frequent periods of continuous banded volcanic tremor occurring, but the amplitudes of earthquakes did not increase. This activity was consistent with explosions from the active cone; however, there was no indication that these bursts are rose more than 4 km a.s.l. Veniaminof remained at Concern Color Code Orange.
Source: US Geological Survey Alaska Volcano Observatory (AVO)
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.