Active volcanoes in the world: December 31, 2014 – January 6, 2015

New activity was observed at 7 volcanoes from December 31, 2014 – January 6, 2015. During the same period, ongoing activity was reported for 11 volcanoes.

New activity/unrest: Chirpoi, Kuril Islands (Russia)  | Etna, Sicily (Italy)  | Fogo, Cape Verde  | Hunga Tonga-Hunga Ha'apai, Tonga Islands  | Klyuchevskoy, Central Kamchatka (Russia)  | Soputan, Sulawesi (Indonesia)  | Tangkubanparahu, Western Java (Indonesia)

Ongoing activity: Aira, Kyushu (Japan)  | Bardarbunga, Iceland  | Chirinkotan, Kuril Islands (Russia)  | Kilauea, Hawaiian Islands (USA)  | Popocatepetl, Mexico  | Sheveluch, Central Kamchatka (Russia)  | Shishaldin, Fox Islands (USA)  | Sinabung, Indonesia  | Slamet, Central Java (Indonesia)  | Suwanosejima, Ryukyu Islands (Japan)  | Zhupanovsky, Eastern Kamchatka (Russia)

New activity/unrest

Chirpoi, Kuril Islands (Russia)
46.525°N, 150.875°E, Summit elev. 742 m

SVERT reported that satellite images over Snow, a volcano of Chirpoi, showed a thermal anomaly on 4 January. Cloud cover obscured views on other days during 30 December-5 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. 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 that on 29 December, a day after a short but intense eruption, cameras viewing Etna recorded small ash emissions from New Southeast Crater (NSEC) and persistent glow from the saddle between the old and new SEC cones at dusk. During the night on 1 and 2 January cameras recorded intermittent flashes from Voragine Crater (one of four summit craters), indicating Strombolian activity there for the first time in nearly two years. At 0530 on 2 January explosions at NSEC generated ash plumes that drifted SW. On the evening of 3 January explosions ejected incandescent material 150 m above the crater rim.

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 BCE. Historical lava flows of basaltic composition cover much of the surface of this massive volcano, whose edifice is the highest and most voluminous in Italy. The Mongibello stratovolcano, truncated by several small calderas, was constructed during the late Pleistocene and Holocene over an older shield volcano. The most prominent morphological feature of Etna is the Valle del Bove, a 5 x 10 km horseshoe-shaped caldera open to the east. 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 (the latter formed in 1978). Flank vents, typically with higher effusion rates, are less frequently active and originate from fissures that open progressively downward from near the summit (usually accompanied by strombolian eruptions at the upper end). Cinder cones are commonly constructed over the vents of lower-flank lava flows. Lava flows extend to the foot of the volcano on all sides and have reached the sea over a broad area on the SE flank.

Fogo, Cape Verde
14.95°N, 24.35°W, Summit elev. 2829 m

Based on gas-monitoring efforts of the Instituto Vulcanológico de Canárias (INVOLCAN) and data from the Toulouse VAAC, the Observatório Vulcanológico de Cabo Verde (OVCV) reported that sulfur dioxide emission rates at Fogo were 1,201-1,368 tons per day during 30-31 December and 1-2 January. A gas plume rose 700-900 m above the cone during 30-31 December and drifted N; on 31 December tephra was ejected 30-40 m away and ash was present on the plume. A lava front near S Ilhéu de Losna had been stagnant for a few days while one near the N part of the town advanced at a reduced speed, overtaking a road and parts of some housing. Temperatures of the lava fronts continued to gradually decrease. During 1-2 January a gas plume rose 400-600 m above the cone and tephra was occasionally ejected 20-25 m away.

Geologic summary: The island of Fogo consists of a single massive stratovolcano that is the most prominent of the Cape Verde Islands. The roughly circular 25-km-wide island is truncated by a large 9-km-wide caldera that is breached to the east and has a headwall 1 km high. The caldera is located asymmetrically NE of the center of the island and was formed as a result of massive lateral collapse of the ancestral Monte Armarelo edifice. A very youthful steep-sided central cone, Pico, rises more than 1 km above the caldera floor to about 100 m above the caldera rim, forming the 2829 m high point of the island. Pico, which is capped by a 500-m-wide, 150-m-deep summit crater, was apparently in almost continuous activity from the time of Portuguese settlement in 1500 CE until around 1760. Later historical lava flows, some from vents on the caldera floor, reached the eastern coast below the breached caldera.

Hunga Tonga-Hunga Ha'apai, Tonga Islands
20.57°S, 175.38°W, Summit elev. 149 m

Based on a pilot observation, the Wellington VAAC reported that an ash plume from Hunga Tonga-Hunga Ha'apai rose to an altitude of 3 km (10,000 ft) a.s.l. on 6 January.

Geologic summary: The small islands of Hunga Tonga and Hunga Ha'apai cap a large seamount located about 30 km SSE of Falcon Island. The two linear andesitic islands are about 2 km long and represent the western and northern remnants of the rim of a largely submarine caldera lying east and south of the islands. Hunga Tonga and Hunga Ha'apai reach an elevation of only 149 m and 128 m above sea level, respectively, and display inward-facing sea cliffs with lava and tephra layers dipping gently away from the submarine caldera. A rocky shoal 3.2 km SE of Hunga Ha'apai and 3 km south of Hunga Tonga marks the most prominent historically active vent. Several submarine eruptions have occurred at Hunga Tonga-Hunga Ha'apai since the first historical eruption in 1912.

Klyuchevskoy, Central Kamchatka (Russia)
56.056°N, 160.642°E, Summit elev. 4754 m

Based on seismic data from KB GS RAS, KVERT reported that seismic activity at Klyuchevskoy began to increase during 19-20 December and then increased again on 31 December. Although cloud cover prevented views of the volcano during 31 December-1 January, a thermal anomaly was detected in satellite images on 1 January, possibly indicating that a Strombolian eruption had begun. The Aviation Color Code was raised to Yellow on 2 January.

Geologic summary: Klyuchevskoy (also spelled 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. It 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 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 the 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.

Soputan, Sulawesi (Indonesia)
1.108°N, 124.73°E, Summit elev. 1784 m

BNPB reported that an eruption at Soputan began at 1447 on 6 January. Observers at a nearby post reported a dense gray-to-black ash plume rising about 6.5 km above the summit and drifting ESE. Lava flows traveled 2 km down the WSW flank. The Alert Level remained at 3 (on a scale of 1-4). Based on ground reports from that same day, the Darwin VAAC reported that a significant eruption generated a plume that rose to an altitude of 8.2 km (27,000 ft) a.s.l. No ash was observed in satellite images due to weather clouds in the area.

Geologic summary: The small Soputan stratovolcano on the southern rim of the Quaternary Tondano caldera on the northern arm of Sulawesi Island is one of Sulawesi's most active volcanoes. The youthful, largely unvegetated volcano rises to 1784 m and is located SW of Sempu volcano. It was constructed at the southern end of a SSW-NNE trending line of vents. During historical time the locus of eruptions has included both the summit crater and Aeseput, a prominent NE-flank vent that formed in 1906 and was the source of intermittent major lava flows until 1924.

Tangkubanparahu, Western Java (Indonesia)
6.77°S, 107.6°E, Summit elev. 2084 m

PVMBG reported that white plumes rose at most 50 m above Tangkubanparahu's Ratu Crater during November-December 2013. Deformation data showed changes and seismicity increased. On 31 December the Alert Level was raised to 2 (on a scale of 1-4). Residents and tourists were warned not approach the crater within a radius of 1.5 km.

Geologic summary: Tangkubanparahu (also known as Tangkuban Perahu) is a broad shield-like stratovolcano overlooking Indonesia's former capital city of Bandung. The volcano was constructed within the 6 x 8 km Pleistocene Sunda caldera, which formed about 190,000 years ago. The volcano's low profile is the subject of legends referring to the mountain of the "upturned boat." The rim of Sunda caldera forms a prominent ridge on the western side; elsewhere the caldera rim is largely buried by deposits of Tangkubanparahu volcano. The dominantly small phreatic historical eruptions recorded since the 19th century have originated from several nested craters within an elliptical 1 x 1.5 km summit depression.

Ongoing activity

Aira, Kyushu (Japan)
31.593°N, 130.657°E, Summit elev. 1117 m

The Tokyo VAAC reported that during 1-6 January plumes from Aira Caldera’s Sakurajima volcano rose to altitudes of 1.5-3 km (5,000-10,000 ft) a.s.l. and drifted SE and S. During 3-5 January pilots observed ash plumes that rose to altitudes of 1.8-4 km (6,000-13,000 ft) a.s.l. On 6 January JMA reported that inflation at Sakurajima had been detected during the previous few days. The Alert Level remained at 3 (on a scale of 1-5).

Geologic summary: The Aira caldera in the northern half of Kagoshima Bay contains the post-caldera Sakurajima volcano, one of Japan's most active. Eruption of the voluminous Ito pyroclastic flow accompanied formation of the 17 x 23 km caldera about 22,000 years ago. The smaller Wakamiko caldera was formed during the early Holocene in the NE corner of the Aira caldera, along with several post-caldera cones. The construction of Sakurajima began about 13,000 years ago on the southern rim of Aira caldera and built an island that was finally joined to the Osumi Peninsula during the major explosive and effusive eruption of 1914. Activity at the Kitadake summit cone ended about 4850 years ago, after which eruptions took place at Minamidake. 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.

Bardarbunga, Iceland
64.63°N, 17.53°W, Summit elev. 2009 m

During 31 December-6 January, IMO maintained Aviation Colour Code Orange due to continued activity at Bárdarbunga’s Holuhraun eruptive fissure. The lava was flowing through a closed channel to the E edge of the lava field, about 15 km from the crater. Lava was also flowing N. Seismicity remained strong and local air pollution from gas emissions persisted. Subsidence continued at a rate of 25 cm/day. The lava field covered 83.4 square kilometers on 6 January.

Preliminary analysis of radar measurements taken during an overflight on 30 December showed that the lava is on average 10 m thick in the E part, 12 m thick at the center, and about 14 m in the W part. The maximum thickness, near the craters, was about 40 m at the E margin of the lava lake. A preliminary estimate for the volume of the lava was 1.1 cubic kilometers. Total subsidence of the Bárdarbunga surface since mid-August was 59 m.

Geologic summary: The large central volcano of Bárdarbunga lies beneath the NW part of the Vatnajökull icecap, NW of Grímsvötn volcano, and contains a subglacial 700-m-deep caldera. Related fissure systems include the Veidivötn and Trollagigar fissures, which extend about 100 km SW to near Torfajökull volcano and 50 km NE to near Askja volcano, respectively. Voluminous fissure eruptions, including one at Thjorsarhraun, which produced the largest known Holocene lava flow on Earth with a volume of more than 21 cu km, have occurred throughout the Holocene into historical time from the Veidivötn fissure system. The last major eruption of Veidivötn, in 1477, also produced a large tephra deposit. The subglacial Loki-Fögrufjöll volcanic system located SW of Bárdarbunga volcano is also part of the Bárdarbunga volcanic system and contains two subglacial ridges extending from the largely subglacial Hamarinn central volcano; the Loki ridge trends to the NE and the Fögrufjöll ridge to the SW. Jökulhlaups (glacier-outburst floods) from eruptions at Bárdarbunga potentially affect drainages in all directions.

Chirinkotan, Kuril Islands (Russia)
48.98°N, 153.48°E, Summit elev. 724 m

SVERT reported that a thermal anomaly over Chirinkotan was detected in satellite images on 30 December. Cloud cover obscured views on the other days during 29 December-5 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.

Kilauea, Hawaiian Islands (USA)
19.421°N, 155.287°W, Summit elev. 1222 m

During 30 December-6 January HVO reported that Kilauea’s 27 June NE-trending lava flow continued to be active with breakout lava flows upslope of the leading front. A narrow lobe of lava that had broken away from the W edge of the flow field below the crack system stalled and by 30 December the front was about 800 m above the intersection of Pahoa Village Road and Highway 130, and 530 m from the Pahoa Marketplace.

The circulating lava lake occasionally rose and fell in the deep pit within Halema'uma'u Crater. Gas emissions remained elevated. The plume from the vent continued to deposit variable amounts of tephra onto nearby areas; smaller particles may have been dropped several kilometers away. At Pu'u 'O'o Crater, glow emanated from several outgassing openings in the crater floor.

Geologic summary: Kilauea volcano, which overlaps the east flank of the massive Mauna Loa shield volcano, has been Hawaii's most active volcano during historical time. Eruptions of Kilauea are prominent in Polynesian legends; written documentation extending back to only 1820 records frequent summit and flank lava flow eruptions that were interspersed with periods of long-term lava lake activity that lasted until 1924 at Halemaumau crater, within the summit caldera. The 3 x 5 km caldera was formed in several stages about 1500 years ago and during the 18th century; eruptions have also originated from the lengthy East and SW rift zones, which extend to the sea on both sides of the volcano. About 90% of the surface of the basaltic shield volcano is formed of lava flows less than about 1100 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.

Popocatepetl, Mexico
19.023°N, 98.622°W, Summit elev. 5426 m

CENAPRED reported that during 31 December-6 January seismicity at Popocatépetl indicated continuing emissions of water vapor and gas, which occasionally contained ash. Cloud cover sometimes prevented views of the crater. Incandescence from the crater was visible on a few nights. Explosions on 1 January at 1948 and on 3 January at 1228 produced ash plumes that rose 600 m and drifted NE. An explosion at 0714 on 4 January generated an ash plume that rose 1.3 km and drifted E. An ash plume later that day rose 1.5 km and drifted NE. The Alert Level remained at Yellow, Phase Two.

Geologic summary: Volcán Popocatépetl, whose name is the Aztec word for smoking mountain, towers to 5426 m 70 km SE of Mexico City to form North America's 2nd-highest volcano. The glacier-clad stratovolcano contains a steep-walled, 400 x 600 m wide crater. The generally symmetrical volcano is modified by the sharp-peaked Ventorrillo on the NW, a remnant of an earlier volcano. At least three previous major cones were destroyed by gravitational failure during the Pleistocene, producing massive debris-avalanche deposits covering broad areas to the south. The modern volcano was constructed south of the late-Pleistocene to Holocene El Fraile cone. Three major plinian eruptions, the most recent of which took place about 800 CE, have occurred from Popocatépetl since the mid Holocene, accompanied by pyroclastic flows and voluminous lahars that swept basins below the volcano. Frequent historical eruptions, first recorded in Aztec codices, have occurred since precolumbian time.

Sheveluch, Central Kamchatka (Russia)
56.653°N, 161.36°E, Summit elev. 3283 m

KVERT reported that during 27 December-2 January lava-dome extrusion onto Sheveluch’s N flank was accompanied by incandescence, hot avalanches, and fumarolic activity. Strong explosions on 26 and 29 December generated ash plumes that rose to altitudes of 6-9 km (19,700-29,500 ft) a.s.l. and drifted 60 km W and 370 km ENE respectively. Satellite images detected a thermal anomaly over the dome during 27-30 December. The Aviation Color Code remained at Orange.

Geologic summary: The high, isolated massif of Sheveluch volcano (also spelled Shiveluch) rises above the lowlands NNE of the Kliuchevskaya volcano group. The 1300 cu km volcano is one of Kamchatka's largest and most active volcanic structures. The summit of roughly 65,000-year-old Stary Shiveluch is truncated by a broad 9-km-wide late-Pleistocene caldera breached to the south. Many lava domes dot its outer flanks. The Molodoy Shiveluch lava dome complex was constructed during the Holocene within the large horseshoe-shaped caldera; Holocene lava dome extrusion also took place on the flanks of Stary Shiveluch. At least 60 large eruptions have occurred during the Holocene, making it the most vigorous andesitic volcano of the Kuril-Kamchatka arc. Widespread tephra layers from these eruptions have provided valuable time markers for dating volcanic events in Kamchatka. Frequent collapses of dome complexes, most recently in 1964, have produced debris avalanches whose deposits cover much of the floor of the breached caldera.

Shishaldin, Fox Islands (USA)
54.756°N, 163.97°W, Summit elev. 2857 m

AVO reported that seismicity at Shishaldin continued to be slightly elevated over background levels during 31 December-6 January. Nothing significant was observed in partly-to-mostly cloudy satellite and web camera images. Minor steam emissions were occasionally recorded by the webcam. The Aviation Color Code remained at Orange and the Volcano Alert Level remained at Watch.

Geologic summary: The beautifully symmetrical volcano of Shishaldin is the highest and one of the most active volcanoes of the Aleutian Islands. The 2857-m-high, glacier-covered volcano is the westernmost of three large stratovolcanoes along an E-W line in the eastern half of Unimak Island. The Aleuts named the volcano Sisquk, meaning "mountain which points the way when I am lost." A steady steam plume rises from its small summit crater. Constructed atop an older glacially dissected volcano, it is Holocene in age and largely basaltic in composition. Remnants of an older ancestral volcano are exposed on the west and NE sides at 1500-1800 m elevation. There are over two dozen pyroclastic cones on its NW flank, which is blanketed by massive aa lava flows. Frequent explosive activity, primarily consisting of strombolian ash eruptions from the small summit crater, but sometimes producing lava flows, has been recorded since the 18th century.

Sinabung, Indonesia
3.17°N, 98.392°E, Summit elev. 2460 m

BNPB reported that an eruption at Sinabung occurred during 0833-0919 on 3 January; this event was larger than the events that had been occurring almost daily. Pyroclastic flows traveled 2-4 km down the flanks and ash plumes rose as high as 3 km. Ashfall was reported in Payung (5 km SSW), Tiganderket (7 km W), Selandi (5 km SSW), Juhar (20 km SW), and Laubaleng (35 km WSW). Since the September 2013 onset of activity, 2,443 people (795 families) still remained displaced.

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 in 1912. No confirmed historical eruptions were recorded prior to explosive eruptions during August-September 2010 that produced ash plumes to 5 km above the summit.

Slamet, Central Java (Indonesia)
7.242°S, 109.208°E, Summit elev. 3428 m

PVMBG reported that during 1 November-5 January white plumes rose at most 1.5 km above Slamet's crater. RSAM values fluctuated but decreased overall in December through 5 January. Deformation and geochemical data showed no significant changes. The Alert Level was lowered to 2 (on a scale of 1-4) on 5 January. Residents and tourists were warned to not approach the crater within a radius of 2 km.

Geologic summary: Slamet, Java's second highest volcano at 3428 m and one of its most active, has a cluster of about three dozen cinder cones on its lower SE-NE flanks and a single cinder cone on the western flank. It is composed of two overlapping edifices, an older basaltic-andesite to andesitic volcano on the west and a younger basaltic to basaltic-andesite one on the east. Gunung Malang II cinder cone on the upper E flank on the younger edifice fed a lava flow that extends 6 km E. Four craters occur at the summit of Gunung Slamet, with activity migrating to the SW over time. Historical eruptions, recorded since the 18th century, have originated from a 150-m-deep, 450-m-wide, steep-walled crater at the western part of the summit and have consisted of explosive eruptions generally lasting a few days to a few weeks.

Suwanosejima, Ryukyu Islands (Japan)
29.638°N, 129.714°E, Summit elev. 796 m

Based on a pilot observations and JMA notices, the Tokyo VAAC reported that on 5 January ash plumes from Suwanosejima rose to altitudes of 1.5-1.8 km (5,000-6,000 ft) a.s.l. and drifted NE and SE.

Geologic summary: The 8-km-long, spindle-shaped island of Suwanosejima in the northern Ryukyu Islands consists of an andesitic stratovolcano with two historically active summit craters. The summit of the volcano is truncated by a large breached crater extending to the sea on the east flank that was formed by edifice collapse. Suwanosejima, one of Japan's most frequently active volcanoes, was in a state of intermittent strombolian activity from Otake, the NE summit crater, that began in 1949 and lasted until 1996, after which periods of inactivity lengthened. The largest historical eruption took place in 1813-14, when thick scoria deposits blanketed residential areas, and the SW crater produced two lava flows that reached the western coast. At the end of the eruption the summit of Otake collapsed forming a large debris avalanche and creating the horseshoe-shaped Sakuchi caldera, which extends to the eastern coast. The island remained uninhabited for about 70 years after the 1813-1814 eruption. Lava flows reached the eastern coast of the island in 1884. Only about 50 persons live on the island.

Zhupanovsky, Eastern Kamchatka (Russia)
53.589°N, 159.15°E, Summit elev. 2899 m

KVERT reported that an eruption at Zhupanovsky continued during 27 December-4 January. Local airline pilots observed explosions and ash plumes that rose to altitudes of 6-9 km (19,700-29,500 ft) a.s.l. on 29 December. That same day ash plumes were observed in satellite images drifting 75 km ENE. The Aviation Color Code remained at Orange.

Geologic summary: The Zhupanovsky volcanic massif consists of four overlapping stratovolcanoes along a WNW-trending ridge. The elongated volcanic complex was constructed within a Pliocene-early Pleistocene caldera whose rim is exposed only on the eastern side. Three of the stratovolcanoes were built during the Pleistocene, the fourth is Holocene in age and was the source of all of Zhupanovsky's historical eruptions. An early Holocene stage of frequent moderate and weak eruptions from 7000 to 5000 years before present (BP) was succeeded by a period of infrequent larger eruptions that produced pyroclastic flows. The last major eruption took place about 800-900 years BP. Historical eruptions have consisted of relatively minor explosions from the third cone.

Source: GVP