Activity for the week of 28 May-3 June 2008
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
| Isla Isabela (Ecuador)
| 0.92°S, 91.408°W
| Elevation 1640 m
Based on information from the Galápagos National Park, observations of satellite imagery, and seismicity, the IG reported that Cerro Azul started to erupt on 29 May from several points along a radial fissure on the SE flank in the Cinco Cerros area. A thermal anomaly was present on satellite imagery at about the same time incandescence was seen through cloudiness in the direction of the volcano from ground observations. On 30 May, a plume, possibly with low ash content, was seen on satellite imagery drifting NW. An overflight and further observations revealed that lava flows traveled about 10 km down the SE flank over older flows from eruptions in 1978 and 1998. According to a news article, the lava flows were active during 29 May-1 June and burned vegetation on the flanks of the volcano.
Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Agence France-Presse (AFP)
| 42.833°S, 72.646°W
| Elevation 1122 m
Based on observations of satellite imagery, SIGMET reports, and pilot observations, the Buenos Aires VAAC reported that during 28 May-3 June continuous ash plumes from Chaitén rose to altitudes of 3-6.4 km (10,000-21,000 ft) a.s.l. and drifted N, NE, E, and SE. Cloudy conditions occasionally inhibited observations.
SERNAGEOMIN reported ash plumes that rose to altitudes of 3.5-4 km (11,200-13,100 ft) a.s.l. and drifted N, NNE, and W during 28 May-2 June. Beaches to the W and N (about 12 km away) continued to accumulate pumice up to 40 cm in diameter carried to the ocean by the Yelcho, Negro, and Chaitén rivers. On 28 May, the ash affected towns and caused airport closings hundreds of kilometers N. A dense layer of mist with suspended ash, about 1.5 km thick and continuous around the volcano on 31 May, resulted in poor visibility. An ash plume at an altitude of 4 km (13,100 ft) a.s.l. was observed above the layer on 30 May. The Alert level remained at Red.
Sources: Servicio Nacional de Geología y Minería (SERNAGEOMIN), Buenos Aires Volcanic Ash Advisory Center (VAAC)
| Halmahera (Indonesia)
| 1.693°N, 127.894°E
| Elevation 1229 m
CVGHM reported incandescence at Dukono's summit during 31 March-24 April. On 25 April, incandescent material was ejected 25 m above the summit. During 30 April-2 May seismicty increased. On 25 May, an ash plume rose to an altitude of 1.4-2.1 km (4,600-6,900 ft) a.s.l. and was accompanied by thunderous and booming sounds. On 29 May, an ash plume rose to an altitude of 2.3 km (7,500 ft) a.s.l. and again was accompanied by thunderous and booming sounds. The Alert Level was raised to 3 (on a scale of 1-4). Residents and visitors were not permitted within 3 km of the summit.
Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM)
| Flores Island (Indonesia)
| 8.542°S, 122.775°E
| Elevation 1703 m
On 29 May, CVGHM raised the Alert Level for Lewotobi to 2 (on a scale of 1-4) due to an increase in seismicity during 12-29 May. White plumes typically rose about 25 m above the crater and drifted E; visual observations indicated no changes.
Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM)
| Kyushu (Japan)
| 31.593°N, 130.657°E
| Elevation 1117 m
Based on information from JMA, the Tokyo VAAC reported that during 30 May-1 June eruption plumes from Sakura-jima rose to altitudes of 2.1-3 km (7,000-10,000 ft) a.s.l. and drifted NW, NE, E, and S.
Source: Tokyo Volcanic Ash Advisory Center (VAAC)
| Komba Island (Indonesia)
| 7.791°S, 123.585°E
| Elevation 633 m
Based on observations of satellite imagery, the Darwin VAAC reported that low-level plumes from Batu Tara rose to altitudes of 1.8-3 km (6,000-10,000 ft) a.s.l. and drifted WNW and NW during 29 May-1 June. On 1 June a thermal anomaly was noted.
Source: Darwin Volcanic Ash Advisory Centre (VAAC)
| 14.473°N, 90.88°W
| Elevation 3763 m
During 28-30 May, INSIVUMEH reported explosions from Fuego and ash plumes that rose to altitudes of 4.1-4.4 km (13,500-14,400 ft) a.s.l. and drifted S and SW. The explosions produced rumbling and degassing sounds, and shock waves detected several kilometers away. Avalanches descended W into the Taniluyá and Santa Teresa ravines. On 2 June, incandescent material was ejected 50-100 m above the crater and a small lava flow traveled 100 m W towards the Santa Teresa ravine. On 3 June, cloudy weather inhibited visual observations, but explosions were heard.
Source: Instituto Nacional de Sismologia, Vulcanologia, Meteorologia, e Hidrologia (INSIVUMEH)
| Eastern Kamchatka (Russia)
| 54.049°N, 159.443°E
| Elevation 1513 m
KVERT reported that seismic activity at Karymsky was slightly above background levels during 22, 25-26, and 28 May and at background levels the other days during 23-30 May. Gas-and-ash explosions that produced plumes to an altitude of 3.4 km (11,200 ft) a.s.l. may have occurred during days of slightly elevated seismicity. The Level of Concern Color Code remained at Orange.
Source: Kamchatkan Volcanic Eruption Response Team (KVERT)
| Hawaiian Islands (USA)
| 19.421°N, 155.287°W
| Elevation 1222 m
Based on visual observations from HVO crews and web camera views, HVO reported that during 28 May-3 June lava flowed SE through a lava tube system underneath Kilauea's Thanksgiving Eve Breakout (TEB) and rootless shield complex to the Waikupanaha ocean entry. Incandescence was occasionally noted from the TEB vent area. Gas continued to jet from a vent about 30 m below Pu'u 'O'o crater's E rim. The sulfur dioxide emission rate was high and fluctuated between 2,740 and 4,700 tonnes per day when measured on 27 and 30 May. The background rate was about 2,000 tonnes per day when measured on 25 May and earlier.
During the reporting period, Kilauea summit earthquakes were located along the S-flank fault and along the E and SW rift zones. The eruption from the vent in Halema'uma'u Crater continued to produce white plumes with minor ash content that drifted mainly SW. During the night incandescence was seen at the base of the plume. Seismic tremor was elevated. The sulfur dioxide emission rate was high and fluctuated between 550 and 1,840 tonnes per day when measured during 27-31 May and 2 June. The background rate was 150-200 tonnes per day.
Source: US Geological Survey Hawaiian Volcano Observatory (HVO)
| New Britain (Papua New Guinea)
| 4.271°S, 152.203°E
| Elevation 688 m
RVO reported steam plumes and roaring noises from Rabaul caldera's Tavurvur cone during 28 May-2 June. Based on observations of satellite imagery and information from RVO, the Darwin VAAC reported that an ash plume rose to an altitude of 2.1 km (7,000 ft) a.s.l. on 2 June and drifted NW.
Sources: Rabaul Volcano Observatory (RVO), Darwin Volcanic Ash Advisory Centre (VAAC)
| Central Kamchatka (Russia)
| 56.653°N, 161.36°E
| Elevation 3283 m
KVERT reported that seismic activity at Shiveluch was slightly above background levels during 27-28 May and at background levels the other days during 23-30 May. Gas-and-ash explosions may have occurred on 22, 27, and 28 May and produced plumes to an altitude of 4.7 km (15,400 ft) a.s.l. According to video footage and visual observations, hot avalanches descended the lava dome and ash plumes rose to an altitude of 3.6 km (11,800 ft) a.s.l. during 26-27 May. Fumarolic activity was noted during 23-27 May. Observations of satellite imagery revealed a daily thermal anomaly in the crater, and an ash-and-steam plume that drifted 17 km SW on 28 May. The Level of Concern Color Code remained at Orange.
Source: Kamchatkan Volcanic Eruption Response Team (KVERT)
| 16.72°N, 62.18°W
| Elevation 915 m
MVO reported that an explosion at Soufrière Hills on 29 May produced an ash plume to an altitude of 3 km (10,000 ft) a.s.l. which drifted SW and generated a pyroclastic flow. The explosion had no precursory seismicity and was heard in multiple areas to the NW. The pyroclastic flow descended a few hundred meters to the W. Observations during an overflight the following day suggested that the explosion and pyroclastic flow originated from the Gages vent.
Source: Montserrat Volcano Observatory (MVO)
| 1.467°S, 78.442°W
| Elevation 5023 m
On 29 May, IG reported that activity from Tungurahua had gradually increased during the previous few weeks. On 23 May, a marked increase in the number of explosions and the intensity and frequency of ash plumes and ashfall was noted. Although visual observations were mostly limited due to cloud cover during 28 May-2 June, steam and ash-and-steam plumes were spotted and rose to altitudes of 6-7 km (19,700-23,000 ft) a.s.l. Ashfall was reported in areas downwind. On 29 May, seismicity increased; several episodes of seismic tremor were detected. Two episodes were accompanied by roaring noises, ash emissions, and incandescent blocks that were ejected from the summit and rolled down the flanks. A thermal anomaly was detected in satellite imagery. Pyroclastic flows descended the N and NW flanks; deposits were observed the next day. On 30 May, emissions of plumes with low ash content were constant and roaring noises were reported. Slight roaring noises were reported on 1 and 3 June.
Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)
| 16.355°S, 70.903°W
| Elevation 5672 m
Based on pilot reports, SIGMET reports, and observations of satellite imagery, the Buenos Aires VAAC reported that during 28-29 May ash plumes from Ubinas rose to altitudes of 5.5-6.1 km (18,000-20,000 ft) a.s.l. and drifted NE and SE. An ash plume rose to an altitude of 4.6 km (15,000 ft) a.s.l. and drifted SSW on 3 June.
Source: Buenos Aires Volcanic Ash Advisory Center (VAAC)
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