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| Anatahan, Mariana Islands
| Guagua Pichincha, Ecuador
| Llaima, Central Chile
Ongoing Activity: | Batu Tara, Komba Island (Indonesia) | Fuego, Guatemala | Kilauea, Hawaii (USA) | Popocatépetl, México | Rabaul, New Britain | Sakura-jima, Kyushu | Santa María, Guatemala | Shiveluch, Central Kamchatka (Russia) | Soufrière Hills, Montserrat | St. Helens, Washington (USA) | Tungurahua, Ecuador
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.
Note: 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.
ANATAHAN Mariana Islands 16.35°N, 145.67°E; summit elev. 790 m
The USGS reported that elevated seismic tremor levels at Anatahan were detected during the last week in January through 5 February. Observations of satellite imagery showed that the lake in the E crater had disappeared, and steam and sulfur dioxide plumes drifted generally W and SW. On 3 February, an ash plume rose to an estimated altitude of below 2.3 km (7,500 ft) a.s.l. and drifted W. On 5 February, the USGS announced that the Volcanic Alert Level was raised to Watch and the Aviation Color Code was raised to Orange as a result of the observed ash emissions.
Geologic Summary. The elongate, 9-km-long island of Anatahan in the central Mariana Islands consists of large stratovolcano with a 2.3 x 5 km, E-W-trending compound summit caldera. The larger western caldera is 2.3 x 3 km wide, and its western rim forms the island's 790-m high point. Ponded lava flows overlain by pyroclastic deposits fill the floor of the western caldera, whose SW side is cut by a fresh-looking smaller crater. The 2-km-wide eastern caldera contained a steep-walled inner crater whose floor prior to the 2003 eruption was only 68 m above sea level. Sparseness of vegetation on the most recent lava flows on Anatahan had indicated that they were of Holocene age, but the first historical eruption of Anatahan did not occur until May 2003, when a large explosive eruption took place forming a new crater inside the eastern caldera.
Anatahan Information from the Global Volcanism Program
GUAGUA PICHINCHA Ecuador 0.171°S, 78.598°W; summit elev. 4784 m
IG reported seven moderate phreatic explosions from Guagua Pichincha on 1 February, following a few weeks of slightly increased internal activity and a few days of almost constant precipitation. IG recommended that visitors stay away from inside the caldera.
Geologic Summary. Guagua Pichincha rises immediately west of Quito, Ecuador's capital city. The broad volcanic massif is cut by a large horseshoe-shaped summit caldera, ~6 km in diameter and 600 m deep, that was breached to the W during a slope failure ~50,000 years ago. Subsequent late-Pleistocene and Holocene eruptions from the central vent consisted of explosive activity with pyroclastic flows accompanied by periodic lava dome growth and destruction. A major eruption in 1660 deposited 30 cm of ash in Quito, but most of the many eruptions since the Spanish colonial era have been minor. The latest eruptive period began with phreatic explosions in 1998. Magmatic eruptions first occurred in October 1999, and intermittent eruptions of varying scale since have blanketed Quito and surrounding towns with ash.
Guagua Pichincha Information from the Global Volcanism Program
LLAIMA Central Chile 38.692°S, 71.729°W; summit elev. 3125 m
SERNAGEOMIN reported that eruptive activity at Llaima continued from the main crater and from multiple areas on the E flank during 30 January-4 February. An overflight on 28 January revealed Strombolian eruptions from a central pyroclastic cone in the main crater accompanied by emissions of ash and ballistic fragments. The craters surrounding the cone were incandescent and emitted bluish sulfur dioxide. Ash-and-gas plumes drifted WSW. A pyroclastic flow deposit was seen on the E flank. During 29 January-1 February, Strombolian eruptions were seen when weather permitted and emissions of ash and gases formed plumes that rose to altitudes of 3.6-6.1 km (11,800-20,000 ft) a.s.l. and drifted SW, SE, NE, and NW. Sporadic activity from the N and S lateral fissures on the E flank was also noted. During 1-2 February, ballistics propelled from the main crater landed both inside and outside of the crater. Strombolian activity declined on 2 February and steam and ash plumes rose to altitudes of 4.6-9.1 km (15,100-29,900 ft) a.s.l. and drifted NW. Emissions from multiple points along fissures on the E flank were noted.
On 3 February, material from intense Strombolian activity was propelled 500 m above the crater floor and fell inside and outside of the crater. Multiple lava flows from the W edge of the main crater descended about 150 m. Incandescent blocks from lava-flow fronts rolled down the flank. Plumes rose to an approximate altitude of 4.6 km (15,100 ft) a.s.l. and drifted WNW. Lava flows originating from a lava lake were observed during an overflight. These flows extended about 1.5-2 km in length and caused strong steam plumes due to their interaction with a glacier. According to a news article, about 20 people were evacuated from an area of La Selva, in the community of Vilcún (43 km W).
Activity was similar on 4 February. A phreatic explosion on the E flank was accompanied by steam plumes and a small pyroclastic flow. Orange ash emissions were noted from the S lateral fissure. Ash plumes from the main crater rose to an altitude of 6 km (19,700 ft) a.s.l. and drifted E.
Geologic Summary. Llaima, one of Chile's largest and most active volcanoes, contains two main historically active craters, one at the summit and the other to the SE. The massive 3,125-m-high, glacier-covered stratovolcano has a volume of 400 cu km. A Holocene edifice built primarily of accumulated lava flows was constructed over an 8-km-wide caldera that formed about 13,200 years ago, following eruption of the 24 cu km Curacautín Ignimbrite. More than 40 scoria cones dot the volcano's flanks. Following the end of an explosive stage about 7,200 years ago, construction of the present edifice began, characterized by Strombolian, Hawaiian, and infrequent subplinian eruptions. Frequent moderate explosive eruptions with occasional lava flows have been recorded since the 17th century.
Llaima Information from the Global Volcanism Program
BATU TARA Komba Island (Indonesia) 7.792°S, 123.579°E; summit elev. 748 m
On 4 February, CVGHM reported that since 9 October 2007, white plumes from Batu Tara were a daily occurrence. On 8 January, gray plumes rose to an altitude of 1.5 km (4,900 ft) a.s.l. and drifted E. On 26 and 30 January, white plumes rose to altitudes of 1.5-1.7 km (4,900-5,600 ft) a.s.l. and also drifted E. The Darwin VAAC reported that eruption plumes were observed from a ship on 31 January, but ash was not identified on satellite imagery. The Alert level remained at 1 (on a scale of 1-4).
Geologic Summary. The small isolated island of Batu Tara in the Flores Sea about 50 km north of Lembata (formerly Lomblen) Island contains a scarp on the eastern side similar to the Sciara del Fuoco of Italy's Stromboli volcano. Vegetation covers the flanks of Batu Tara to within 50 m of the 748-m-high summit. Batu Tara lies north of the main volcanic arc and is noted for its potassic leucite-bearing basanitic and tephritic rocks. The first historical eruption from Batu Tara, during 1847-52, produced explosions and a lava flow.
Batu Tara Information from the Global Volcanism Program
FUEGO Guatemala 14.473°N, 90.880°W; summit elev. 3763 m
Geologic Summary. Volcán Fuego, one of Central America's most active volcanoes, is one of three large stratovolcanoes overlooking Guatemala's former capital, Antigua. The scarp of an older edifice, Meseta, lies between 3,763-m-high Fuego and its twin volcano to the N, Acatenango. Construction of Meseta volcano continued until the late Pleistocene or early Holocene, after which growth of the modern Fuego volcano continued the southward migration of volcanism that began at Acatenango. Frequent vigorous historical eruptions have been recorded at Fuego since the onset of the Spanish era in 1524, and have produced major ashfalls, along with occasional pyroclastic flows and lava flows. The last major explosive eruption from Fuego took place in 1974, producing spectacular pyroclastic flows visible from Antigua.
Fuego Information from the Global Volcanism Program
KILAUEA Hawaii (USA) 19.421°N, 155.287°W; summit elev. 1222 m
Based on observations during overflights, and web camera views when weather permitted, HVO reported that during 30 January-5 February activity from Kilauea's fissure segment D was concentrated at the Thanksgiving Eve Breakout (TEB) shield and satellitic shields to the SE. Lava flows issued from the tops and flanks of the shields. Lava in the original perched lava channel, formed from the 21 July fissure eruption, overflowed the N end. On 30 January, the channelized 'a'a lava flow from a rootless shield that collapsed on 26 January advanced, burning small kipukas and another small area of the Royal Gardens subdivision. The lava flow was inactive the next day. During 30-31 February, the rootless shields at the SE end of the field (within 2 km of fissure D) issued abundant lava flows overnight. The lava pond within the Shield-4 collapse overflowed several times; lava flows advanced S.
Incandescence was observed in Pu'u 'O'o crater for less than 10 minutes at a time every day during the reporting period. A few small earthquakes were located beneath Halema'uma'u crater and along the S-flank faults, SW rift zone, and upper E rift zone.
Geologic Summary. Kilauea, one of five coalescing volcanoes that comprise the island of Hawaii, is one of the world's most active volcanoes. Eruptions at Kilauea originate primarily from the summit caldera or along one of the lengthy E and SW rift zones that extend from the caldera to the sea. About 90% of the surface of Kilauea is formed of lava flows less than about 1,100 years old; 70% of the volcano's surface is younger than 600 years. A long-term eruption from the East rift zone that began in 1983 has produced lava flows covering more than 100 sq km, destroying nearly 200 houses and adding new coastline to the island.
Kilauea Information from the Global Volcanism Program
POPOCATEPETL México 19.023°N, 98.622°W; summit elev. 5426 m
CENAPRED reported that emissions of steam and gas from Popocatépetl were visible during 30 January-5 February. The plumes occasionally contained slight amounts of ash. On 4 February, ash emissions were accompanied by an explosion that propelled incandescent fragments 300 m from the crater.
Geologic Summary. Popocatépetl, whose name is the Aztec word for smoking mountain, towers to 5,426 m 70 km SE of Mexico City and is North America's second-highest volcano. Frequent historical eruptions have been recorded since the beginning of the Spanish colonial era. A small eruption on 21 December 1994 ended five decades of quiescence. Since 1996 small lava domes have incrementally been constructed within the summit crater and destroyed by explosive eruptions. Intermittent small-to-moderate gas-and-ash eruptions have continued, occasionally producing ashfall in neighboring towns and villages.
Popocatépetl Information from the Global Volcanism Program
RABAUL New Britain 4.271°S, 152.203°E; summit elev. 688 m
RVO reported that gray and brown ash plumes and steam plumes from Rabaul caldera's Tavurvur cone rose to altitudes of 0.9-2.7 km (3,000-8,900 ft) a.s.l. and drifted E and SE during 31 January-5 February. Incandescence from the center of the crater was visible almost every night. On 1 February, ashfall was reported in Kokopo, about 20 km SE. Roaring noises were heard from near-by areas during 1-3 February. On 4 February, a strong smell of hydrogen sulfide gas was reported from Rabaul Town (3-5 km NW).
Geologic Summary. The low-lying Rabaul caldera on the tip of the Gazelle Peninsula at the NE end of New Britain forms a broad sheltered harbor. The outer flanks of the 688-m-high asymmetrical pyroclastic shield volcano are formed by thick pyroclastic-flow deposits. The 8 x 14 km caldera is widely breached on the E, where its floor is flooded by Blanche Bay. Two major Holocene caldera-forming eruptions at Rabaul took place as recently as 3,500 and 1,400 years ago. Three small stratovolcanoes lie outside the northern and NE caldera rims. Post-caldera eruptions built basaltic-to-dacitic pyroclastic cones on the caldera floor near the NE and western caldera walls. Several of these, including Vulcan cone, which was formed during a large eruption in 1878, have produced major explosive activity during historical time. A powerful explosive eruption in 1994 occurred simultaneously from Vulcan and Tavurvur volcanoes and forced the temporary abandonment of Rabaul city.
Source: Steve Saunders and Herman Patia, Rabaul Volcano Observatory
Rabaul Information from the Global Volcanism Program
SAKURA-JIMA Kyushu 31.585°N, 130.657°E; summit elev. 1117 m
Based on information from JMA, the Tokyo VAAC reported that explosions from Sakura-jima on 3 February produced plumes that rose to altitudes of 1.5-2.7 km (5,000-9,000 ft) a.s.l. and drifted SE. Ash was not detected on satellite imagery. On 5 February, a pilot reported an ash plume at an altitude of 2.1 km (7,000 ft) a.s.l.
Geologic Summary. Sakura-jima, one of Japan's most active volcanoes, is a post-caldera cone of the Aira caldera at the northern half of Kagoshima Bay. Eruption of the voluminous Ito pyroclastic flow was associated with the formation of the 17 x 23-km-wide Aira caldera about 22,000 years ago. The construction of Sakura-jima began about 13,000 years ago and built an island that was finally joined to the Osumi Peninsula during the major explosive and effusive eruption of 1914. Activity at the Kita-dake summit cone ended about 4,850 years ago, after which eruptions took place at Minami-dake. Frequent historical eruptions, recorded since the 8th century, have deposited ash on Kagoshima, one of Kyushu's largest cities, located across Kagoshima Bay only 8 km from the summit. The largest historical eruption took place during 1471-76.
Sakura-jima Information from the Global Volcanism Program
SANTA MARIA Guatemala 14.756°N, 91.552°W; summit elev. 3772 m
Based on observations of satellite imagery, the Washington VAAC reported that gas plumes with possible ash content from Santa María's Santiaguito lava dome complex drifted SW on 30 January. Ash plumes drifted WNW on 3 February.
Geologic Summary. Symmetrical, forest-covered Santa María volcano is one of a chain of large stratovolcanoes that rises dramatically above the Pacific coastal plain of Guatemala. The stratovolcano has a sharp-topped, conical profile that is cut on the SW flank by a large, 1-km-wide crater, which formed during a catastrophic eruption in 1902 and extends from just below the summit to the lower flank. The renowned Plinian eruption of 1902 followed a long repose period and devastated much of SW Guatemala. The large dacitic Santiaguito lava-dome complex has been growing at the base of the 1902 crater since 1922. Compound dome growth at Santiaguito has occurred episodically from four westward-younging vents, accompanied by almost continuous minor explosions and periodic lava extrusion, larger explosions, pyroclastic flows, and lahars.
Santa María Information from the Global Volcanism Program
SHIVELUCH Central Kamchatka (Russia) 56.653°N, 161.360°E; summit elev. 3283 m
KVERT reported that seismic activity at Shiveluch was slightly above background levels during 25 January-1 February. Based on seismic interpretation, ash plumes rose to an altitude of 3.9 km (12,800 ft) a.s.l. daily. Fumarolic activity was noted on 24, 29, and 30 January. According to observations of satellite imagery, a thermal anomaly was present in the crater every day during the reporting period. The Level of Concern Color Code remained at Orange.
Geologic Summary. The high, isolated massif of Shiveluch volcano (also spelled Sheveluch) rises above the lowlands NNE of the Kliuchevskaya volcano group and forms one of Kamchatka's largest and most active volcanoes. The currently active Molodoy Shiveluch lava-dome complex was constructed during the Holocene within a large breached caldera formed by collapse of the massive late-Pleistocene Strary Shiveluch volcano. At least 60 large eruptions of Shiveluch have occurred during the Holocene, making it the most vigorous andesitic volcano of the Kuril-Kamchatka arc. Frequent collapses of lava-dome complexes, most recently in 1964, have produced large debris avalanches whose deposits cover much of the floor of the breached caldera. Intermittent explosive eruptions began in the 1990s from a new lava dome that began growing in 1980. The largest historical eruptions from Shiveluch occurred in 1854 and 1964.
Shiveluch Information from the Global Volcanism Program
SOUFRIERE HILLS Montserrat 16.72°N, 62.18°W; summit elev. 915 m
MVO reported that that during 30 January-5 February the lava dome at Soufrière Hills changed very little, based on visual observations during an over flight on 30 January and from multiple locations. Seismic activity was very low and low-level rockfall activity continued. Fumarolic activity on the N and E flanks continued. Active fumaroles were also noted in the Galway's area to the S of the dome and W in the Gages Wall area. The Alert Level remained elevated at 4 (on a scale of 0-5).
Geologic Summary. The complex dominantly andesitic Soufrière Hills volcano occupies the southern half of the island of Montserrat. The summit area consists primarily of a series of lava domes emplaced along an ESE-trending zone. English's Crater, a 1-km-wide crater breached widely to the E, was formed during an eruption about 4,000 years ago in which the summit collapsed, producing a large submarine debris avalanche. Block-and-ash flow and surge deposits associated with dome growth predominate in flank deposits at Soufrière Hills. Non-eruptive seismic swarms occurred at 30-year intervals in the 20th century, but with the exception of a 17th-century eruption that produced the Castle Peak lava dome, no historical eruptions were recorded on Montserrat until 1995. Long-term small-to-moderate ash eruptions beginning in that year were later accompanied by lava-dome growth and pyroclastic flows that forced evacuation of the southern half of the island and ultimately destroyed the capital city of Plymouth, causing major social and economic disruption.
Soufrière Hills Information from the Global Volcanism Program
ST. HELENS Washington (USA) 46.20°N, 122.18°W; summit elev. 2549 m
Data from deformation-monitoring instruments indicated that during 30 January-5 February lava-dome growth at Mount St. Helens continued. Seismicity persisted at low levels, punctuated by M 1.5-2.5, and occasionally larger, earthquakes. Clouds occasionally inhibited visual observations.
Geologic Summary. Prior to 1980, Mount St. Helens formed a conical, youthful volcano sometimes known as the Fuji-san of America. During the 1980 eruption the upper 400 m of the summit was removed by slope failure, leaving a 2 x 3.5 km horseshoe-shaped crater now partially filled by a lava dome. Mount St. Helens was formed during nine eruptive periods beginning about 40-50,000 years ago, and has been the most active volcano in the Cascade Range during the Holocene. The modern edifice was constructed during the last 2,200 years, when the volcano produced basaltic as well as andesitic and dacitic products from summit and flank vents. Historical eruptions in the 19th century originated from the Goat Rocks area on the N flank, and were witnessed by early settlers.
St. Helens Information from the Global Volcanism Program
TUNGURAHUA Ecuador 1.467°S, 78.442°W; summit elev. 5023 m
IG reported that although visual observations were limited due to cloud cover, ash plumes were spotted and rose to altitudes of 6-9 km (19,700-29,500 ft) a.s.l. during 30 January-5 February. Ash plumes drifted mainly W, NW, and E, and ashfall was also reported in areas to the SW, N, and NE. Roaring noises and "cannon shots" were heard almost everyday and the seismic network detected between 65-208 explosions daily.
On 30 January, incandescence at the summit was observed at night and incandescent blocks that were propelled from the summit by explosions rolled 600 m down the W flank. Explosions rattled windows as far away as the Tungurahua Observatory (OVT) in Guadalupe, about 13 km NW. A lahar descended the Mandur drainage, to the NW. On 1 and 4 February, incandescence at the summit was again noted and incandescent blocks traveled down the flanks. On 4 February, heavy ashfall to the SW was reported and explosions rattled windows in near-by areas. On 5 February, ashfall was reported in areas to the NW.
Geologic Summary. The steep-sided Tungurahua stratovolcano towers more than 3 km above its northern base. It sits ~140 km S of Quito, Ecuador's capital city, and is one of Ecuador's most active volcanoes. Historical eruptions have all originated from the summit crater. They have been accompanied by strong explosions and sometimes by pyroclastic flows and lava flows that reached populated areas at the volcano's base. The last major eruption took place from 1916 to 1918, although minor activity continued until 1925. The latest eruption began in October 1999 and prompted temporary evacuation of the town of Baños on the N side of the volcano.
Tungurahua Information from the Global Volcanism Program
Additional Reports of Volcanic Activity by Country
The following websites have frequently updated activity reports on volcanoes in addition to those that meet the criteria for inclusion in the Weekly Volcanic Activity Report. The websites are organized by country and are maintained by various agencies.