Active volcanoes in the world: January 15 – January 21, 2014

New activity was observed at 6 volcanoes in last 7 days, ongoing activity was reported for 10 volcanoes. This report covers active volcanoes in the world from January 15 – January 21, 2014 based on Smithsonian/USGS criteria.

New activity/unrest: | El Misti, Peru | Grímsvötn, Iceland | Pacaya, Guatemala | San Cristóbal, Nicaragua | San Miguel, El Salvador | Sinabung, Sumatra (Indonesia)

Ongoing activity: | Chirinkotan, Kuril Islands | Chirpoi, Kuril Islands (Russia) | Colima, México border | Fuego, Guatemala | Karymsky, Eastern Kamchatka (Russia) | Kilauea, Hawaii (USA) | Nishimo-shima, Japan | Puyehue-Cordón Caulle, Central Chile | Sakurajima, Kyushu | Shiveluch, Central Kamchatka (Russia)

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 23:00 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

El MISTI, Peru 
16.294°S, 71.409°W; summit elev. 5822 m

Instituto Geofísico del Perú (IGP) reported that seismicity at El Misti increased during January, and a seismic swarm consisting of 119 volcano-tectonic events was detected during 14-15 January. Despite the increase, activity remained at a low level.

Geologic summary: El Misti, Peru's most well-known volcano, is a symmetrical andesitic stratovolcano with nested summit craters that towers above the city of Arequipa. The modern symmetrical cone, constructed within a small 1.5 x 2 km wide summit caldera that formed between about 13,700 and 11,300 years ago, caps older Pleistocene volcanoes that underwent caldera collapse about 50,000 years ago. A large scoria cone has grown with the 830-m-wide outer summit crater of El Misti. At least 20 tephra-fall deposits and numerous pyroclastic-flow deposits have been documented during the past 50,000 years, including a pyroclastic flow that traveled 12 km to the south about 2000 years ago. El Misti's most recent activity has been dominantly pyroclastic, and strong winds have formed a parabolic dune field of volcanic ash extending up to 20 km downwind. An eruption in the 15th century affected Inca inhabitants living near the volcano. Some reports of historical eruptions may represent increased fumarolic activity.

GRIMSVOTN, Iceland 
64.42°N, 17.33°W; summit elev. 1725 m

According to the Icelandic Meteorological Office, the level of the Skaftá river at Sveinstindur and electrical conductivity both rose during 18-19 January indicating a glacial outburst flood (jokulhlaup), originating from Grímsvötn's western Skaftá ice cauldron. The jokulhlaup was unconfirmed without visual observations, however. Flood waters peaked on 20 January and then began to subside on 21 January. The report noted that floods in Skaftá source from two ice cauldrons formed by persistent geothermal activity beneath Vatnajökull. The cauldrons drain an average every two years, producing floods of up to 1,500 cubic meters per second.

Geologic summary: Grímsvötn, Iceland's most frequently active volcano in historical time, lies largely beneath the vast Vatnajökull icecap. The caldera lake is covered by a 200-m-thick ice shelf, and only the southern rim of the 6 x 8 km caldera is exposed. The geothermal area in the caldera causes frequent jökulhlaups (glacier outburst floods) when melting raises the water level high enough to lift its ice dam. Long NE-SW-trending fissure systems extend from the central volcano. The most prominent of these is the noted Laki (Skaftar) fissure, which extends to the SW and produced the world's largest known historical lava flow during an eruption in 1783. The 15-cu-km basaltic Laki lavas were erupted over a 7-month period from a 27-km-long fissure system. Extensive crop damage and livestock losses caused a severe famine that resulted in the loss of one-fifth of the population of Iceland.

PACAYA, Guatemala 
14.381°N, 90.601°W; summit elev. 2552 m

INSIVUMEH reported that during 16-20 January gas plumes rose from Pacaya and a lava flow on the S flank remained active. A report on 21 January noted that the S-flank lava flow was 3.6 km long and continued to slowly advance, burning vegetation between the Rodeo and Los Pocitos roads. Volcanologists observed that the cone in Mackenney Crater had been completely destroyed, leaving a deep crater that produced fumarolic activity.

Geologic summary: Eruptions from Pacaya, one of Guatemala's most active volcanoes, are frequently visible from Guatemala City, the nation's capital. Pacaya is a complex volcano constructed on the southern rim of the 14 x 16 km Pleistocene Amatitlan caldera. A cluster of dacitic lava domes occupies the caldera floor. The Pacaya massif includes the Cerro Grande lava dome and a younger volcano to the SW. Collapse of Pacaya volcano about 1,100 years ago produced a debris-avalanche deposit that extends 25 km onto the Pacific coastal plain and left an arcuate somma rim inside which the modern Pacaya volcano (MacKenney cone) grew. During the past several decades, activity at Pacaya has consisted of frequent Strombolian eruptions with intermittent lava flow extrusion on the flanks of MacKenney cone, punctuated by occasional larger explosive eruptions.

SAN CRISTOBAL, Nicaragua 
12.702°N, 87.004°W; summit elev. 1745 m

INETER reported that seismic tremor at San Cristóbal increased at 0340 on 17 January; RSAM values increased from a baseline of 70 to 460 units. Twelve gas emissions were observed between 1259 and 1315, and RSAM climbed to 649 units. A report at 1700 noted that RSAM values decreased to 100 and no additional gas emissions were observed. The next day, 18 January, RSAM values fluctuated between 90 and 190 units.

Geologic summary: The San Cristóbal volcanic complex, consisting of five principal volcanic edifices, forms the NW end of the Marrabios Range. The symmetrical 1,745-m-high youngest cone, San Cristóbal itself (also known as El Viejo), is Nicaragua's highest volcano and is capped by a 500 x 600 m wide crater. El Chonco, with several flank lava domes, is located 4 km to the west of San Cristóbal; it and the eroded Moyotepe volcano, 4 km to the NE of San Cristóbal, are of Pleistocene age. Volcán Casita contains an elongated summit crater and lies immediately E of San Cristóbal; Casita was the site of a catastrophic landslide and lahar in 1998. The Plio-Pleistocene La Pelona caldera is located at the eastern end of the San Cristóbal complex. Historical eruptions from San Cristóbal, consisting of small-to-moderate explosive activity, have been reported since the 16th century. Some other 16th-century eruptions attributed to Casita volcano are uncertain and may pertain to other Marrabios Range volcanoes.

SAN MIGUEL, El Salvador 
13.434°N, 88.269°W; summit elev. 2130 m

SNET reported that during 15-20 January RSAM values at San Miguel fluctuated between 14 and 97, except for a period starting at 1500 on 19 January where the values were 102-215. Gas emissions were characterized by light gray plumes that rose 100-250 m above the crater and drifted S and SW.

Geologic summary: The symmetrical cone of San Miguel volcano, one of the most active in El Salvador, rises from near sea level to form one of the country's most prominent landmarks. A broad, deep crater that has been frequently modified by historical eruptions (recorded since the early 16th century) caps the truncated summit of the towering volcano, which is also known locally as Chaparrastique. Radial fissures on the flanks of the basaltic volcano have fed a series of fresh lava flows, including several erupted during the 17th-19th centuries that reached beyond the base of the volcano on the N, W, and SE sides. The SE-flank lava flows are the largest and form broad sparsely vegetated lava fields.

SINABUNG, Sumatra (Indonesia) 
3.17°N, 98.392°E; summit elev. 2460 m

PVMBG described activity at Sinabung during 10-17 January based on observations from a post in the Ndokum Siroga village, 8.5 km away. Each day brownish white or gray and white ash plumes rose as high as 5 km, pyroclastic flows traveled 0.5-4.5 km E, SE, and S, and incandescent material was observed on the S and SE flanks as far as 3 km. Seismicity remained high, with constant tremor, hybrid earthquakes indicating a growing lava dome, and volcanic earthquakes. The number of low-frequency earthquakes continued to drop, however. The Alert Level remained at 4 (on a scale of 1-4).

Geologic summary: Gunung Sinabung is a Pleistocene-to-Holocene stratovolcano with many lava flows on its flanks.  The migration of summit vents along a N-S line gives the summit crater complex an elongated form.  The youngest crater of this conical, 2460-m-high andesitic-to-dacitic volcano is at the southern end of the four overlapping summit craters.  An unconfirmed eruption was noted in 1881, and solfataric activity was seen at the summit and upper flanks of Sinabung in 1912, although no confirmed historical eruptions were recorded prior to 2010.

Ongoing activity

CHIRINKOTAN. Kuril Islands 
48.980°N, 153.480°E; summit elev. 724 m

SVERT reported that a thermal anomaly over Chirinkotan was observed in satellite images on 15 and 17 January. Gas-and-steam emissions were also observed on 17 January. Cloud cover obscured views on the other days during 14-20 January. The Aviation Color Code remained at Yellow.

Geologic summary:  The small, mostly unvegetated 3-km-wide island of Chirinkotan occupies the far end of an E-W-trending volcanic chain that extends nearly 50 km west of the central part of the main Kuril Islands arc. Chirinkotan is the emergent summit of a volcano that rises 3000 m from the floor of the Kuril Basin. A small 1-km-wide caldera about 300-400 m deep is open to the SE. Lava flows from a cone within the breached crater reached the north shore of the island. Historical eruptions have been recorded at Chirinkotan since the 18th century. Fresh lava flows also descended the SE flank of Chirinkotan during an eruption in the 1880s that was observed by the English fur trader Captain Snow.

CHIRPOI, Kuril Islands (Russia)
46.525°N, 150.875°E; summit elev. 742 m

SVERT reported that a thermal anomaly over Snow, a volcano of Chirpoi, was detected in satellite images during 15-16 January. Cloud cover obscured views on the other days during 14-20 January. The Aviation Color Code remained at Yellow.

Geologic summary: Chirpoi, a small island lying between the larger islands of Simushir and Urup, contains a half dozen volcanic edifices constructed within an 8-9 km wide, partially submerged caldera. The southern rim of the caldera is exposed on nearby Brat Chirpoev Island. Two volcanoes on Chirpoi Island have been historically active. The symmetrical Cherny volcano, which forms the 691 m high point of the island, erupted twice during the 18th and 19th centuries. The youngest volcano, Snow, originated between 1770 and 1810. It is composed almost entirely of lava flows, many of which have reached the sea on the southern coast. No historical eruptions are known from 742-m-high Brat Chirpoev, but its youthful morphology suggests recent strombolian activity.

COLIMA, México 
19.514°N, 103.62°W; summit elev. 3850 m

The Washington VAAC reported intermittent ash emissions from Colima on 21 January: an ash puff drifted S at an altitude of 4.9 km (16,000 ft) a.s.l., a second ash puff drifted SSW, and a third ash puff drifted S.

Geologic summary: The Colima volcanic complex is the most prominent volcanic center of the western Mexican Volcanic Belt. It consists of two southward-younging volcanoes, Nevado de Colima (the 4,320 m high point of the complex) on the N and the historically active Volcán de Colima on the S. Volcán de Colima (also known as Volcán Fuego) is a youthful stratovolcano constructed within a 5-km-wide caldera, breached to the S, that has been the source of large debris avalanches. Major slope failures have occurred repeatedly from both the Nevado and Colima cones, and have produced a thick apron of debris-avalanche deposits on three sides of the complex. Frequent historical eruptions date back to the 16th century. Occasional major explosive eruptions (most recently in 1913) have destroyed the summit and left a deep, steep-sided crater that was slowly refilled and then overtopped by lava dome growth.

FUEGO, Guatemala 
14.473°N, 90.880°W; summit elev. 3763 m

INSIVUMEH reported that during 16-18 January explosions at Fuego produced ash plumes that rose 450-550 m above the crater. A lava flow in the Trinidad (S) drainage was 400 m long and generated avalanches. Other avalanches from the crater descended the Taniluya (SW), Ceniza (SSW), Trinidad, Las Lajas (SE), and Honda (E) drainages. Explosions during 19-20 January produced ash plumes that rose 500-800 m and drifted 10 km SE. Incandescent material was ejected 100-150 high and avalanches continued to descend multiple 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.

KARYMSKY, Eastern Kamchatka (Russia) 
54.05°N, 159.45°E; summit elev. 1536 m

KVERT reported that Vulcanian and Strombolian activity at Karymsky continued during 10-17 January. Satellite images detected a bright thermal anomaly on the volcano daily. On 19 January satellite images showed an ash plume that rose to altitudes of 3-3.5 km (8,200-9,800 ft) a.s.l. and drifted 40 km SSE. 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.

KILAUEA, Hawaii (USA) 
19.421°N, 155.287°W; summit elev. 1222 m

During 15-21 January 2014 HVO reported that the circulating lava lake occasionally rose and fell in the deep pit within Kilauea's Halema'uma'u Crater. A "deflation-inflation" event, or DI, began on 17 January and by 21 January the lava-lake level had dropped more than 20 m to about 70 m below the crater floor. The plume from the vent continued to deposit variable amounts of ash, spatter, and Pele's hair onto nearby areas. At Pu'u 'O'o Crater, glow emanated from spatter cones on the N and S portions of the crater floor. The 7.5-km-long Kahauale’a 2 lava flow (based on a satellite image from 17 January), fed by the NE spatter cone, was active with scattered break-out flows and burned the forest N of Pu'u 'O'o. On 19 January the N side of the NE spatter cone collapsed, possibly due to lower lava levels as a result of the DI event, exposing a small lava pond.

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.

NISHIMO-SHIMA, Izu, Volcano, and Mariana Islands (Japan) 
27.274°N, 140.882°E; summit elev. 38 m

Based on satellite analysis, the Tokyo VAAC reported that on 21 January a possible ash plume from Nishino-shima rose 0.9 km (3,000 ft) a.s.l. and drifted E. An image acquired a few hours later showed that ash had dissipated.

Geologic summary: The small island of Nishino-shima was recently enlarged when it was joined to several new islands that formed during an eruption in 1973-74. Water discoloration has been observed on several occasions since. The 700-m-wide island is the summit of a massive submarine volcano that has prominent satellitic peaks to the south, west, and NE. The summit of the southern cone rises to within 214 m of the sea surface 9 km SSE of Nishino-shima.

PUYEHUE-CORDON CAULLE, Central Chile
40.590°S, 72.117°W; summit elev. 2236 m

Based on analyses of satellite images, the Buenos Aires VAAC reported that on 16 January steam-and-gas emissions with minor amounts of ash rose from the Cordón Caulle rift zone, part of the Puyehue-Cordón Caulle volcanic complex, to an altitude of 2.4 km (8,000 ft) a.s.l. The plume quickly dissipated. The Alert Level remained at Green (lowest on a four-color scale).

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.

SAKURAJIMA, Kyushu
31.585°N, 130.657°E; summit elev. 1117 m

The Tokyo VAAC reported that an explosion from Sakurajima on 17 January generated plumes that rose to altitude of 2.4-2.7 km (8,000-9,000 ft) a.s.l. and drifted SE.

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.

SHIVELUCH, Central Kamchatka (Russia) 
56.653°N, 161.360°E; summit elev. 3283 m

KVERT reported that during 10-17 January a newer lava dome continued to extrude onto the NW part of Shiveluch's older lava dome. Lava-dome extrusion was accompanied by hot avalanches, incandescence, and fumarolic activity. Moderate ash explosions generated ash plumes that rose to altitudes of 4-5 km (13,100-16,400) a.s.l. A thermal anomaly was detected daily in satellite images, and ash plumes that rose to an altitude of 6 km (19,700) a.s.l. drifted 110 km ENE on 10 January. Explosions on 12 January generated ash plumes that rose to altitudes of 8-9 km (26,200-29,500 ft) a.s.l., and drifted 400 km SW during 12-13 January. 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.

Source: GVP