New activity was observed at 2 volcanoes between December 11 and 17. During the same period, ongoing activity was observed at 9 volcanoes.
New activity/unrest: | Kliuchevskoi, Central Kamchatka (Russia) | Puyehue-Cordón Caulle, Central Chile
Ongoing activity: | Chirinkotan, Kuril Islands | Chirpoi, Kuril Islands (Russia) | Etna, Sicily (Italy) | Fuego, Guatemala | Karymsky, Eastern Kamchatka (Russia) | Kilauea, Hawaii (USA) | Sakura-jima, Kyushu | Shiveluch, Central Kamchatka (Russia) | Sinabung, Sumatra (Indonesia)
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.
KLIUCHEVSKOI, Central Kamchatka (Russia)
56.057°N, 160.638°E; summit elev. 4850 m
KVERT reported that the explosive eruption at Kliuchevskoi continued during 6-13 December. Seismicity increased on 6 December but then declined on 10 December; during this period video images showed ash plumes rising to altitudes of 5-6 km (16,400-19,700 ft) a.s.l. Satellite images detected a weak thermal anomaly daily, and ash plumes that drifted 1,200 km E during 6-8 December, NW during 9-10 December, and E and SE during 10-11 December. The Aviation Color Code remained at Orange.
Geologic summary: Kliuchevskoi is Kamchatka's highest and most active volcano. Since its origin about 6000 years ago, the beautifully symmetrical, 4835-m-high basaltic stratovolcano has produced frequent moderate-volume explosive and effusive eruptions without major periods of inactivity. Kliuchevskoi rises above a saddle NE of sharp-peaked Kamen volcano and lies SE of the broad Ushkovsky massif. More than 100 flank eruptions have occurred at Kliuchevskoi during the past roughly 3000 years, with most lateral craters and cones occurring along radial fissures between the unconfined NE-to-SE flanks of the conical volcano between 500 m and 3600 m elevation. The morphology of its 700-m-wide summit crater has been frequently modified by historical eruptions, which have been recorded since the late-17th century. Historical eruptions have originated primarily from the summit crater, but have also included numerous major explosive and effusive eruptions from flank craters.
PUYEHUE-CORDON CAULLE, Central Chile
40.590°S, 72.117°W; summit elev. 2236 m
A scientist from NOAA's National Environmental Satellite, Data, and Information Service (NESDIS) reported that an ash cloud drifting NNE from the Cordón Caulle rift zone, part of the Puyehue-Cordón Caulle volcanic complex, was visible in satellite images starting at 0800 on 14 December. The scientist noted that, although it appeared to be a fresh emission, the cloud was likely re-suspended ash from strong southerly winds. In addition, no other evidence of renewed activity was detected.
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.
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 9, 12, and 15 December. Cloud cover obscured views on the other days during 10-16 December. 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 12-13 and 15 December. Cloud cover obscured views on the other days during 10-16 December. 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.
ETNA, Sicily (Italy)
37.734°N, 15.004°E; summit elev. 3330 m
INGV reported on the 20th paroxysm in 2013 from Etna’s New Southeast Crater (NSEC) began with a strong explosion at 0925 on 14 December from a vent near the NE rim which generated an ash plume that rose 2 km. Intermittent ash emission gradually turned into Strombolian activity. After 1413 the activity intensified; small ash puffs were produced and Strombolian explosions ejected incandescent pyroclastics onto the flanks of the cone. Over the next few hours activity continued to intensify and a diffuse ash plume drifted ESE. At 2323 lava overflowed the SE crater rim and flowed towards the Valle del Bove. During the night explosive activity continued to intensify, and by 0330 on 15 December Strombolian activity was intense and virtually continuous. After 0500 explosive activity started to diminish, and at 0550 the volcanic tremor amplitude and the intensity and frequency of Strombolian explosions showed a sharp drop. Explosive activity continued to produce copious amounts of ash until about 0830. According to a news article, the ash emissions caused the cancellation of more than 20 flights in and out of the Catania airport.
At 0610 and 0633 two vents opened within the deep trench cutting the SE flank of the NSEC cone (where lava was still flowing from the crater since the previous evening), the first just a few tens of meters below the crater rim, the second about 100 m further downslope. Both vents initially produced lava fountains for a few minutes, with jets a few tens of meters high, and then produced lava flows that descended through the trench.
Between 0945 on 15 December and the morning of 16 December ash emission varied in frequency and intensity, related to variations in the intensity of the Strombolian activity at NSEC. During the afternoon and evening of 15 December explosive activity lasted a few to a few tens of minutes and Strombolian activity became significantly more intense or passed into pulsating, low lava fountains. The more intense periods produced greater amounts of ash leading to ashfall in populated areas on the E and SE flank, from the Milo-Zafferana area toward the Ionian coast. At night during 15-16 December lava flows continued to flow towards the Valle del Bove. A shift in wind direction caused ashfall in areas SE, S, and SW.
On 15 December small and periodic ash emissions also occurred from Northeast Crater. Small thermal anomalies detected with a thermal camera were detected during 15-16 December.
Strombolian activity at the NSEC continued through 16 December at a slowly decreasing rate and with numerous minor intensifications that generated diluted ash plumes. Lava effusion also gradually diminished, but at about 1430 on 16 December, a short fissure opened on the lower NE flank of the NSEC cone, producing a small lava flow which advanced a few hundred meters. Explosive activity finally ceased around midnight on 17 December. Very slow lava effusion continued, at a gradually decreasing rate, from the fissure on the NE flank of the NSEC cone, through the night of 17-18 December.
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.
14.473°N, 90.880°W; summit elev. 3763 m
In a special report INSIVUMEH noted that activity at Fuego had increased on 15 December. Lava flows were 500 m long in the Ceniza drainage (SSW), and their emission rate rate had increased. Blocks from lava-flow fronts reached vegetated areas. Six to eight explosions per hour produced ash plumes that rose 550 m and drifted 8 km. The explosions generated shock waves and rattled buildings in nearby villages. The next day lava flows were 600 m long in the Ceniza drainage. Explosions generated ash plumes that rose 450 m and drifted W and SW.
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 moderate seismic activity at Karymsky was detected during 6-13 December, and Vulcanian and Strombolian activity continued. Satellite images detected a bright thermal anomaly on the volcano daily, and ash plumes that drifted 150 km E and SE during 6-7 and 10 December. 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 11-17 December HVO reported that the circulating lava lake occasionally rose and fell in the deep pit within Kilauea's Halema'uma'u Crater. 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 7.3-km-long Kahauale’a 2 lava flow, fed by the NE spatter cone, was active with scattered break-out flows and burned the forest N of Pu'u 'O'o. The flow was most active about 5 km NE of Pu'u 'O'o, based on satellite images from 10 December.
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.
31.585°N, 130.657°E; summit elev. 1117 m
The Tokyo VAAC reported that during 11-17 December explosions at Sakura-jima generated plumes that rose to altitudes of 1.2-3.4 km (4,000-11,000 ft) a.s.l. and drifted E, SE, and S. JMA reported that six explosions from Showa Crater ejected tephra as far as 1,800 m during 13-16 December. A six-minute-long explosion was detected on 14 December. The Alert Level remained at 3 (on a scale of 1-5).
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
Based on visual observations and analyses of satellite data, KVERT reported that during 6-13 December a new lava dome extruded onto the NW part of Shiveluch's older lava dome. Moderate ash explosions generated ash plumes that rose to altitudes of 4-5 km (13,100-16,400) a.s.l. Lava-dome extrusion was accompanied by hot avalanches, incandescence, and fumarolic activity. A thermal anomaly was detected daily in satellite images. On 17 December satellite images showed an ash plume drifting 50 km NW at altitudes of 4.5-5 km (14,800-16,400 ft) a.s.l. 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.
SINABUNG, Sumatra (Indonesia)
3.17°N, 98.392°E; summit elev. 2460 m
PVMBG reported that observers in Ndokum Siroga, about 8.5 km away, noted gray plumes rising 1 km above Sinabung on 6 December. Grayish-white plumes rose as high as 400 m on 7 December, and dense white plumes also rose as high as 400 m the next day. Dense grayish-to-white plumes rose 70-200 m on 9 December. White plumes rose 100-150 m above the crater during 10-13 December. Tremor during 6-13 December was recorded continuously, with varying amplitude. The number of low-frequency earthquakes significantly increased on 7 December, and the number of hybrid earthquakes increased the next day. RSAM values had steadily increased since 28 November. 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.