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| Hierro, Canary Islands (Spain)
| Nyamuragira, Democratic Republic of Congo
Ongoing Activity: | Etna, Sicily (Italy) | Fuego, Guatemala | Karymsky, Eastern Kamchatka (Russia) | Kilauea, Hawaii (USA) | Kizimen, Eastern Kamchatka (Russia) | Manam, Northeast of New Guinea (SW Pacific) | Poás, Costa Rica | Puyehue-Cordón Caulle, Central Chile | Sakura-jima, Kyushu | Shiveluch, Central Kamchatka (Russia) | 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.
HIERRO Canary Islands (Spain) 27.73°N, 18.03°W; summit elev. 1500 m
Instituto Geográfico Nacional (IGN) reported that during 9-15 November the submarine eruption continued S of El Hierro Island; mean amplitude of tremor was similar to that of the previous week. During the period, 245 seismic events were recorded, most of them located offshore to the N of the island, at depths of 16-23 km. Twenty one of these events were felt by residents at a maximum intensity value of IV-V using EMS-98 (European Macroseismic Scale). The maximum magnitude was 4.6, for an event located 2.5 km offshore to the N at 21 km depth on 11 November, and was the largest of the 11,604 total events detected since 16 July. GPS deformation analysis continued to show different behaviors between N and S stations; N stations showed deformations to the N up to the time of the M 4.6 event, when the deformation then changed to S. Stations located in the S showed deformation trends to the N.
On 9 November, access to two creeks (Tacorón and Punta Naos) in the S of the island was prohibited due to the possibility of significant concentration of volcanic gases. On 14 November, residents of La Restinga were allowed to return to their homes. That same day, many big steaming lava blocks (more than 1 m in diameter) were observed over the submarine emission center.
Geologic Summary. The triangular island of Hierro is the SW-most and least studied of the Canary Islands. The massive Hierro shield volcano is truncated by a large NW-facing escarpment formed as a result of gravitational collapse of El Golfo volcano about 130,000 years ago. The steep-sided 1500-m-high scarp towers above a low lava platform bordering 12-km-wide El Golfo Bay, and three other large submarine landslide deposits occur to the SW and SE. Three prominent rifts oriented NW, NE, and south at 120 degree angles form prominent topographic ridges. The subaerial portion of the volcano consists of flat-lying Quaternary basaltic and trachybasaltic lava flows and tuffs capped by numerous young cinder cones and lava flows. Holocene cones and flows are found both on the outer flanks and in the El Golfo depression. Hierro contains the greatest concentration of young vents in the Canary Islands. Uncertainty surrounds the report of an historical eruption in 1793.
Hierro Information from the Global Volcanism Program
NYAMURAGIRA Democratic Republic of Congo 1.408°S, 29.20°E; summit elev. 3058 m
According to GORISK (an initiative of the National Museum of Natural History, Luxembourg and Royal Museum for Central Africa, Belgium), the eruption at Nyamuragira that began on 6 November, after two days of intense seismic activity, was located along a fissure 11-12 km ENE of the main crater, close to one of the 1989 eruption sites.
Virunga National Park staff had previously been observing the eruption from a hilltop in Rumangabo, but on 9 November the staff and rangers traveled to the site. After a 3-hour hike, the team viewed the eruption from the S and noted roaring and lava fountains, as well as thunder and lightning. The observers also noted that the ground was covered by black pumice. On 11 November about 100 people, including staff, rangers, carpenters, porters, and volcanologists, traveled to a similar but safer location to set up a camp for visitors. The eruption site was described as a flat area with a 500-1,000-m-long fissure, oriented perpendicular to the Albertine (Western) rift. Lava fountains rose as high as 300 m above a cinder cone. Slow-moving lava traveled N.
GORISK noted that radar images acquired on 11 November showed the largest deformation ever detected by the method (InSAR) since the early 1990's over Nyamuragira. A very preliminary analysis of the observed deformation suggested an affected area of more than 250 square kilometers. The ground rose more than 50 cm at the eruptive site where the spatter cone was developing. Another 15 cm of deformation was detected within the Nyamuragira caldera accompanied by deflation on the flanks. Satellite images acquired on 12 November showed that the lava flow had traveled approximately 11.5 km during the six days of the eruption.
Geologic Summary. Africa's most active volcano, Nyamuragira (Also spelled Nyamulagira) is a massive basaltic shield volcano N of Lake Kivu and NW of Nyiragongo volcano. Lava flows from Nyamuragira cover 1,500 sq km of the East African Rift. The 3058-m-high summit is truncated by a small 2 x 2.3 km summit caldera that has walls up to about 100 m high. About 40 historical eruptions have occurred since the mid-19th century within the summit caldera and from numerous fissures and cinder cones on the volcano's flanks. A lava lake in the summit crater, active since at least 1921, drained in 1938. Twentieth-century flank lava flows extend more than 30 km from the summit, reaching as far as Lake Kivu.
Nyamuragira Information from the Global Volcanism Program
ETNA Sicily (Italy) 37.734°N, 15.004°E; summit elev. 3330 m
Sezione di Catania - Osservatorio Etneo reported that the eighteenth paroxysmal eruptive episode of 2011 took place at the New SE Crater (New SEC) of Etna during the morning of 15 November. Thermal monitoring cameras at the observatory in Catania and at Montagnola, about 3.5 km S of the summit craters, recorded a small thermal anomaly at the lower end of the eruptive fissure on the SE flank of the cone at about 0700. The anomaly slowly grew in size and temperature, caused by the emission and expansion of a small lava flow. Mild Strombolian activity commenced at 0900 from within the New SEC, and spattering began from several vents along the fissure on the SE flank of the cone. This activity continued for nearly three hours, while increasing very slowly, and the lava flow spread out into several branches at the SE base of the cone, advancing only a few hundred meters. At about 1155, the activity markedly and rapidly increased both within the crater and along the fissure, and just after 1200 lava fountains and ash emissions rose from the crater. Lava fountains then rose from vents along the SE flank fissure. Bombs and scoria fell into the cone.
At 1230 ash emissions significantly increased, especially from a vent located in the SE portion of the New SEC, and a plume of ash and gas rose several kilometers above the summit and drifted SE. The most intense phase of the eruption occurred between 1245 and 1315 when jets heavily laden with incandescent bombs rose as high as 800 m above the crater. Pyroclastic material fell onto the New SEC cone, areas well beyond the base, and the nearby old SEC cone. During this phase explosions occurred from a vent on the N flank of the New SEC cone, likely the same vent that emitted small lava flows on 28 September and 8 October. At about 1325 the activity started to diminish and ceased abruptly at 1329, but was followed by passive ash emissions that lasted until just after 1400. Weak and discontinuous spattering accompanied by slow lava effusion continued for a few hours from a single vent in the central portion of the eruptive fissure on the SE flank of the New SEC cone.
Lava flows from the eruption traveled less than 4 km toward the floor of the Valle del Bove, immediately to the N of the Serra Giannicola ridge, stagnating to the SW of Monte Centenari. The New SEC grew in height by 10 m on the S side, bringing the total height of the cone to about 180-200 m above its base. Ash and lapilli deposits affected the SE flank, including the towns of Zafferana Etnea (10 km SE) and Acireale (20 km SE).
Geologic Summary. Mount Etna, towering above Catania, Sicily's second largest city, has one of the world's longest documented records of historical volcanism, dating back to 1500 BC. Historical lava flows cover much of the surface of this massive basaltic stratovolcano, the highest and most voluminous in Italy. Two styles of eruptive activity typically occur at Etna. Persistent explosive eruptions, sometimes with minor lava emissions, take place from one or more of the three prominent summit craters, the Central Crater, NE Crater, and SE Crater. Flank eruptions, typically with higher effusion rates, occur less frequently and originate from fissures that open progressively downward from near the summit. A period of more intense intermittent explosive eruptions from Etna's summit craters began in 1995. The active volcano is monitored by the Instituto Nazionale di Geofisica e Volcanologia (INGV) in Catania.
Etna Information from the Global Volcanism Program
FUEGO Guatemala 14.473°N, 90.880°W; summit elev. 3763 m
INSIVUMEH reported that activity at Fuego increased during 8-9 November. Explosions produced shock waves that were detected up to 15 km away, rumbling sounds, and ash plumes that rose 1.5-2 km above the crater and drifted 20 km SW. Ash fell on the SW flank in Panimaché (6 km SW), Morelia (7 km SW), Sangre de Cristo (8 km WSW), and Santa Sofía. Block avalanches descended the flanks. During 9-10 November explosions generated ash plumes that rose 600-800 m above the crater and drifted 10 km S and SW. Avalanches descended the SW flank towards the Taniluya and Ceniza drainages.
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
KARYMSKY Eastern Kamchatka (Russia) 54.05°N, 159.45°E; summit elev. 1536 m
KVERT reported that seismic activity continued at a moderate level at Karymsky during 4-11 November, and indicated that possible ash plumes rose to an altitude of 3.5 km (11,500 ft) a.s.l. Satellite imagery showed either no activity, possibly due to cloud cover. The Aviation Color Code remained at Orange.
Geologic Summary. Karymsky, the most active volcano of Kamchatka's eastern volcanic zone, is a symmetrical stratovolcano constructed within a 5-km-wide caldera that formed about 7,600-7,700 radiocarbon years ago. Construction of the Karymsky stratovolcano began about 2,000 years later. The latest eruptive period began about 500 years ago, following a 2,300-year quiescence. Much of the cone is mantled by lava flows less than 200 years old. Historical eruptions have been Vulcanian or Vulcanian-Strombolian with moderate explosive activity and occasional lava flows from the summit crater. Most seismicity preceding Karymsky eruptions has originated beneath Akademia Nauk caldera, which is located immediately S of Karymsky volcano and erupted simultaneously with Karymsky in 1996.
Karymsky Information from the Global Volcanism Program
KILAUEA Hawaii (USA) 19.421°N, 155.287°W; summit elev. 1222 m
During 9-15 November, 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 emanated 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. Pahoehoe flows, fed through lava tubes from the fissure, continued to be active about 4.7 km SE of Pu'u 'O'o based on an overflight on 12 November and satellite images. Incandescence from a skylight on the lava tube was also observed.
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
KIZIMEN Eastern Kamchatka (Russia) 55.130°N, 160.32°E; summit elev. 2376 m
KVERT reported moderate seismic activity at Kizimen during 4-11 November and that a thermal anomaly on the volcano was detected daily in satellite images. A large lava flow on the NE and E flanks continued to effuse and the crater was incandescent at night during 2-3 and 6-9 November. Video observations showed gas-and-steam activity during 4-9 November. The Aviation Color Code remained at Orange.
Geologic Summary. Kizimen is an isolated, conical stratovolcano that is morphologically similar to Mount St. Helens prior to its 1980 eruption. The summit of Kizimen consists of overlapping lava domes, and blocky lava flows descend the flanks of the volcano, which is the westernmost of a volcanic chain north of Kronotsky volcano. The 2,376-m-high Kizimen was formed during four eruptive cycles beginning about 12,000 years ago and lasting 2,000-3,500 years. The largest eruptions took place about 10,000 and 8300-8400 years ago, and three periods of longterm lava-dome growth have occurred. The latest eruptive cycle began about 3,000 years ago with a large explosion and was followed by lava-dome growth lasting intermittently about 1,000 years. An explosive eruption about 1,100 years ago produced a lateral blast and created a 1.0 x 0.7 km wide crater breached to the NE, inside which a small lava dome (the fourth at Kizimen) has grown. A single explosive eruption, during 1927-28, has been recorded in historical time.
Kizimen Information from the Global Volcanism Program
MANAM Northeast of New Guinea (SW Pacific) 4.080°S, 145.037°E; summit elev. 1807 m
Based on analysis of satellite imagery and a pilot observation, the Darwin VAAC reported that on 11 November an ash plume from Manam rose to an altitude of 3 km (10,000 ft) a.s.l. and drifted about 90 km NE.
Geologic Summary. The 10-km-wide island of Manam, lying 13 km off the northern coast of mainland Papua New Guinea, is one of the country's most active volcanoes. Four large radial valleys extend from the unvegetated summit of the conical 1807-m-high basaltic-andesitic stratovolcano to its lower flanks. These "avalanche valleys," regularly spaced 90 degrees apart, channel lava flows and pyroclastic avalanches that have sometimes reached the coast. Two summit craters are present; both are active, although most historical eruptions have originated from the southern crater, concentrating eruptive products during much of the past century into the SE avalanche valley. Frequent historical eruptions, typically of mild-to-moderate scale, have been recorded at Manam since 1616. Occasional larger eruptions have produced pyroclastic flows and lava flows that reached flat-lying coastal areas and entered the sea, sometimes impacting populated areas.
Manam Information from the Global Volcanism Program
POAS Costa Rica 10.20°N, 84.233°W; summit elev. 2708 m
OVSICORI-UNA reported that during October fumarolic activity at Poás continued with bluish gas plumes rising from the lava dome; plumes rose more than 1 km and were reported by residents in Valle Central. Towards the end of the month, the fumarolic activity as well as incandescence from the lava dome decreased. The new craters at the N base of the dome united into a crater that was 25 m long and 7-10 m wide. Phreatic activity continued to occur from Laguna Caliente, the summit lake. The lake was 55 degrees Celsius, and the level had risen 22 cm between 14 September and 27 October.
Geologic Summary. The broad, well-vegetated edifice of Poás, one of the most active volcanoes of Costa Rica, contains three craters along a N-S line. The frequently visited multi-hued summit crater lakes of the basaltic-to-dacitic volcano, which is one of Costa Rica's most prominent natural landmarks, are easily accessible by vehicle from the nearby capital city of San José. A N-S-trending fissure cutting the 2,708-m-high complex stratovolcano extends to the lower northern flank, where it has produced the Congo stratovolcano and several lake-filled maars. The southernmost of the two summit crater lakes, Botos, is cold and clear and last erupted about 7,500 years ago. The more prominent geothermally heated northern lake, Laguna Caliente, is one of the world's most acidic natural lakes, with a pH of near zero. It has been the site of frequent phreatic and phreatomagmatic eruptions since the first historical eruption was reported in 1828. Poás eruptions often include geyser-like ejection of crater-lake water.
Poás Information from the Global Volcanism Program
PUYEHUE-CORDON CAULLE Central Chile 40.590°S, 72.117°W; summit elev. 2236 m
Based on seismicity during 9-13 November, 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 9-10 November clouds prevented observations with an area web camera, but on 9 November satellite imagery showed an ash plume that drifted and dissipated to the E. During 11-12 November mostly gray plumes observed with the web camera rose 4-7 km above the crater. During the night the crater was incandescent and small explosions were observed. Satellite imagery showed ash plumes drifting 90 km NE on 11 November and 400 km SE on 12 November. Ash fell in areas on the border of Chile and Argentina at Paso Samore on 12 November. Cloud cover prevented web camera views on 13 November, but satellite imagery showed a plume drifting 250 km NE. A gray plume rose 6.5 km above the crater on 14 November. That same day a plume identified in satellite imagery drifted 200 km NW and ash clouds drifted from the SE to the NE. The Alert Level remained at Red.
Geologic Summary. The Puyehue-Cordón Caulle volcanic complex (PCCVC) is a large NW-SE-trending late-Pleistocene to Holocene basaltic-to-rhyolitic transverse volcanic chain SE of Lago Ranco. The 1799-m-high Pleistocene Cordillera Nevada caldera lies at the NW end, separated from Puyehue stratovolcano at the SE end by the Cordón Caulle fissure complex. The Pleistocene Mencheca volcano with Holocene flank cones lies NE of Puyehue. The basaltic-to-rhyolitic Puyehue volcano is the most geochemically diverse of the PCCVC. The flat-topped, 2236-m-high Puyehue volcano was constructed above a 5-km-wide caldera and is capped by a 2.4-km-wide summit caldera of Holocene age. Lava flows and domes of mostly rhyolitic composition are found on the eastern flank of Puyehue. Historical eruptions originally attributed to Puyehue, including major eruptions in 1921-22 and 1960, are now known to be from the Cordón Caulle rift zone. The Cordón Caulle geothermal area, occupying a 6 x 13 km wide volcano-tectonic depression, is the largest active geothermal area of the southern Andes volcanic zone.
Puyehue-Cordón Caulle 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 during 9-12 and 14-15 November explosions from Sakura-jima produced plumes that rose to altitudes of 1.5-3 km (5,000-10,000 ft) a.s.l. and drifted W, S, and SE. On 14 November a pilot reported that an ash plume rose to an altitude of 1.5 km (5,000 ft) a.s.l. and drifted SE. Satellite imagery during 14-15 November showed ash emissions that later dissipated.
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
SHIVELUCH Central Kamchatka (Russia) 56.653°N, 161.360°E; summit elev. 3283 m
KVERT reported that moderate seismic activity was detected at Shiveluch during 4-11 November, and indicated that possible ash plumes rose to a maximum altitude of 4.5 km (14,800 ft) a.s.l. Ground-based observers noted that a viscous lava flow continued to effuse in the crater formed during a 2010 eruption. Strong fumarolic activity at the lava dome was observed during 2-3 and 5-9 November; cloud cover prevented observations on the other days. Satellite imagery showed a daily thermal anomaly over the lava dome and gas-and-steam plumes containing small amounts of ash that drifted 25 km E on 5 November. The Aviation 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
TUNGURAHUA Ecuador 1.467°S, 78.442°W; summit elev. 5023 m
The Washington VAAC reported that on 9 November an ash plume from Tungurahua was identified by a pilot. A later report stated that IG noted no ash emissions from Tungurahua since June, and that only gas-and-steam emissions had been observed that day.
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.