Active volcanoes in the world: January 22 – January 28, 2014

New activity was observed at 2 volcanoes in last 7 days, ongoing activity was reported for 14 volcanoes. This report covers active volcanoes in the world from January 22 – January 28, 2014 based on Smithsonian/USGS criteria.

New activity/unrest: | Asosan, Kyushu | Sinabung, Sumatra (Indonesia)

Ongoing activity: | Chirinkotan, Kuril Islands | Chirpoi, Kuril Islands (Russia) | Dukono, Halmahera | Etna, Sicily (Italy) | Gorely, Southern Kamchatka (Russia) | Karymsky, Eastern Kamchatka (Russia) | Kilauea, Hawaii (USA) | Nishino-shima, Japan | Reventador, Ecuador | Sakurajima, Kyushu | Santa María, Guatemala | Shiveluch, Central Kamchatka (Russia) | Suwanosejima, Ryukyu Islands and Kyushu | White Island, New Zealand

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

ASOSAN, Kyushu 
32.881°N, 131.106°E; summit elev. 1592 m

JMA reported that seismicity at Asosan increased from 21 to 23 January, and then decreased on 24 January. On 23 January a volcanologist observed ash plumes rising from the central vent on the crater floor. The Alert Level remained at 2 (on a scale of 1-5).

Geologic summary: The 24-km-wide Aso caldera was formed during four major explosive eruptions from 300,000 to 80,000 years ago. These produced voluminous pyroclastic flows that covered much of Kyushu. A group of 17 central cones was constructed in the middle of the caldera, one of which, Naka-dake, is one of Japan's most active volcanoes. It was the location of Japan's first documented historical eruption in 553 AD. The Naka-dake complex has remained active throughout the Holocene. Several other cones have been active during the Holocene, including the Kometsuka scoria cone as recently as about 210 AD. Historical eruptions have largely consisted of basaltic to basaltic-andesite ash emission with periodic Strombolian and phreatomagmatic activity. The summit crater of Naka-dake is accessible by toll road and cable car, and is one of Kyushu's most popular tourist destinations.

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

Badan Nacional Penanggulangan Bencana (BNPB) reported that between 1200 and 1800 on 23 January pyroclastic flows traveled 1.5 km down Sinabung's S flank. The number of displaced people reached 28,715 (9,045 families) in 42 evacuation centers. Based on webcam views, satellite images, ground reports, and altitude and drift directions derived from wind data, the Darwin VAAC reported that during 22-23 and 25-27 January ash plumes rose to an altitude 5.2 km (17,000 ft) a.s.l. and drifted 35-185 km N, NE, and E.

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 21 January. Cloud cover obscured views during 22-27 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 21-23 January. Cloud cover obscured views during 24-27 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.

DUKONO, Halmahera 
1.68°N, 127.88°E; summit elev. 1335 m

Based on analyses of satellite imagery and wind data, the Darwin VAAC reported that during 20-23 January ash plumes from Dukono rose to an altitude of 3 km (10,000 ft) a.s.l. and drifted 75-157 km NE. On 28 January ash plumes rose to an altitude of 4.3 km (14,000 ft) a.s.l. and drifted almost 140 km E.

Geologic summary: Reports from this remote volcano in northernmost Halmahera are rare, but Dukono has been one of Indonesia's most active volcanoes. More-or-less continuous explosive eruptions, sometimes accompanied by lava flows, occurred from 1933 until at least the mid-1990s, when routine observations were curtailed. During a major eruption in 1550, a lava flow filled in the strait between Halmahera and the N-flank cone of Gunung Mamuya. Dukono is a complex volcano presenting a broad, low profile with multiple summit peaks and overlapping craters. Malupang Wariang, 1 km SW of Dukono's summit crater complex, contains a 700 x 570 m crater that has also been active during historical time.

ETNA, Sicily (Italy) 
37.734°N, 15.004°E; summit elev. 3330 m

INGV reported that during 4-13 January nearly continuous emissions of reddish ash from Etna's Northeast Crater were visible. Strong degassing continued at least through 22 January. Strombolian activity at New Southeast Crater (NSEC) began on the evening of 21 January, following 20 days of quiet. Some explosions generated very small ash emissions that barely rose above the crater rim. Late on 22 January a small lava flow from the vent on the high E flank of the NSEC cone traveled a few hundred meters in a few hours. Strombolian explosions ejected incandescent pyroclastic material onto the cone flanks. The frequency and intensity of the explosions decreased early on 23 January, and the lava flow stopped advancing. At 0105 a small puff of gas and/or ash from the E base of the cone heralded a new lava flow that traveled W towards the Valle del Bove. Weak Strombolian activity and the advancing lava flow continued during 24-28 January, although on 25 January the amount of ash produced by the Strombolian activity increased. On 26 January an ash plume drifted E. By evening the intensity of the Strombolian activity as well as the amount of ash in the emissions decreased. The lava flow was 4 km long.

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.

GORELY, Southern Kamchatka (Russia) 
52.558°N, 158.03°E; summit elev. 1829 m

KVERT reported that activity at Gorely decreased significantly in December 2013; volcanic tremor ceased being detected on 12 December, and the temperature of the thermal anomaly decreased during 12-15 December. No thermal anomaly was detected in January 2014, but weak seismicity continued along with gas-and-steam emissions. On 23 January the Aviation Color Code was lowered to Green (on a four-color scale).

Geologic summary: Gorely volcano, one of the most active in southern Kamchatka, consists of five small overlapping stratovolcanoes constructed along a WNW-ESE line within a large 9 x 13.5 km late-Pleistocene caldera. The massive Gorely complex contains 11 summit and 30 flank craters. During the early Holocene, activity was characterized by frequent mild eruptions with occasional larger explosions and lava flows that filled in the caldera. Quiescent periods became longer between 6,000 and 2,000 years ago, after which the activity was mainly explosive. About 600-650 years ago intermittent strong explosions and lava flow effusion accompanied frequent mild eruptions. Historical eruptions have consisted of vulcanian and phreatic explosions of moderate volume.

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 17-24 January. Satellite images detected a bright thermal anomaly on the volcano daily, and ash plumes that drifted 110 km E. 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 22-28 January 2014 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 7.8-km-long Kahauale’a 2 lava flow (based on mapping from 24 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 23 January a small lava flow also oozed out of the SE spatter cone. During 23-26 January lava rose in the westernmost spatter cone and flowed down the N flank.

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.

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

A photo and video posted by the Japan Coast Guard showed that on 20 January the Niijima portion of Nishinoshima was larger than the original island; the two islands had merged on 24 December 2013. White and brown plumes rose from Niijima and the water to the SW was discolored.

Geologic summary: The small island of Nishinoshima 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.

REVENTADOR, Ecuador 
0.077°S, 77.656°W; summit elev. 3562 m

Based on information from IG, the Washington VAAC reported that on 22 January an ash plume from Reventador rose to an altitude of km (12,000 ft) a.s.l. Ash was not identified in satellite images. IG noted that an explosions lasting several minutes was recorded.

Geologic summary: Reventador is the most frequently active of a chain of Ecuadorian volcanoes in the Cordillera Real, well E of the principal volcanic axis. It is a forested stratovolcano that rises above the remote jungles of the western Amazon basin. A 3-km-wide caldera breached to the E was formed by edifice collapse and is partially filled by a young, unvegetated stratovolcano that rises about 1,300 m above the caldera floor. Reventador has been the source of numerous lava flows as well as explosive eruptions that were visible from Quito in historical time. Frequent lahars in this region of heavy rainfall have constructed a debris plain on the eastern floor of the caldera.

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

JMA reported that during 20-24 January three explosions from Sakurajima's Showa Crater ejected tephra as far as 1,300 m. An explosion on 22 January generated a small pyroclastic flow that traveled 500 m SE, and tephrafall to the S. The Alert Level remained at 3 (on a scale of 1-5). The Tokyo VAAC reported that on 22 January a plume rose to an altitude of 3 km (10,000 ft) a.s.l. and drifted S. That same day pilots observed ash plumes that rose to altitudes of 3.7-4.9 km (12,000-16,000 ft) a.s.l. and drifted S and ESE. On 24 January a pilot observed an ash plume drifting NE at an altitude of 1.2 km (4,000 ft) a.s.l.

Geologic summary: Sakura-jima, one of Japan's most active volcanoes, is a post-caldera cone of the Aira caldera at the northern half of Kagoshima Bay. Eruption of the voluminous Ito pyroclastic flow was associated with the formation of the 17 x 23-km-wide Aira caldera about 22,000 years ago. The construction of Sakura-jima began about 13,000 years ago and built an island that was finally joined to the Osumi Peninsula during the major explosive and effusive eruption of 1914. Activity at the Kita-dake summit cone ended about 4,850 years ago, after which eruptions took place at Minami-dake. Frequent historical eruptions, recorded since the 8th century, have deposited ash on Kagoshima, one of Kyushu's largest cities, located across Kagoshima Bay only 8 km from the summit. The largest historical eruption took place during 1471-76.

SANTA MARIA, Guatemala 
14.756°N, 91.552°W; summit elev. 3772 m

In a special report on 23 January, INSIVUMEH noted that a lava flow on the SE flank of Santa María's Santiaguito lava-dome complex became active; collapses from the lava-flow front generated avalanches and small pyroclastic flows that reached the base of the volcano. The report also noted that in recent months activity at Santa María was high, with explosions sometimes ranging from 40 to 45 explosions per day, generating ash plumes that rose 3-3.4 km. A change in wind direction on 23 January pushed the ash plume E and NE, causing ashfall in areas 10 km away. On 24 January explosions produced ash plumes that rose 500-700 m above the complex. A lava flow on the NE flank generated avalanches. Explosions during 27-28 January produced ash plumes that rose 600-800 m and drifted E, NE, and SW, causing ashfall in Santa María de Jesús (SE) and the El Rosario Palajunoj finca.

Geologic summary: Symmetrical, forest-covered Santa María volcano is one of a chain of large stratovolcanoes that rises dramatically above the Pacific coastal plain of Guatemala. The stratovolcano has a sharp-topped, conical profile that is cut on the SW flank by a large, 1-km-wide crater, which formed during a catastrophic eruption in 1902 and extends from just below the summit to the lower flank. The renowned Plinian eruption of 1902 followed a long repose period and devastated much of SW Guatemala. The large dacitic Santiaguito lava-dome complex has been growing at the base of the 1902 crater since 1922. Compound dome growth at Santiaguito has occurred episodically from four westward-younging vents, accompanied by almost continuous minor explosions and periodic lava extrusion, larger explosions, pyroclastic flows, and lahars.

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

KVERT reported that during 17-24 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 rose to altitudes of 7-8 km (23,000-26,200 ft) a.s.l. during 20-21 January and drifted 300 km WNW during 20-22 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.

SUWANOSEJIMA, Kyushu 
29.635°N, 129.716°E; summit elev. 799 m

Based on information from JMA, the Tokyo VAAC reported that explosions from Suwanosejima on 24 January generated a plume that rose to an altitude 1.8 km (6,000 ft) a.s.l.

Geologic summary: The 8-km-long, spindle-shaped island of Suwanose-jima in the northern Ryukyu Islands consists of an andesitic stratovolcano with two historically active summit craters. Only about 50 persons live on the sparsely populated island. 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. Suwanose-jima, one of Japan's most frequently active volcanoes, was in a state of intermittent strombolian activity from On-take (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 On-take 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.

WHITE ISLAND, New Zealand 
37.52°S, 177.18°E; summit elev. 321 m

On 22 January, the GeoNet Data Centre reported that the Volcanic Alert Level for White Island remained at 1 and the Aviation Colour Code remained Green. Since a moderate eruption on 11 October 2013, seismicity had remained at low levels while gas flux was elevated. Sulfur dioxide flux ranged from 133 to 924 tonnes per day, higher than levels before 2012 when daily averages were less than 300 tonnes. The level of the water in Crater Lake continued to rise, and was about 5 m deeper than in late 2013. Temperature measurements with a recently acquired thermal Infrared camera confirm that hot gases were rising from vents on the lava dome; temperatures at the vents were 200-330 degrees Celsius, and over 400 degrees at one vent.

Geologic summary: The uninhabited 2 x 2.4 km White Island, one of New Zealand's most active volcanoes, is the emergent summit of a 16 x 18 km submarine volcano in the Bay of Plenty about 50 km offshore of North Island. The 321-m-high island consists of two overlapping stratovolcanoes; the summit crater appears to be breached to the SE because the shoreline corresponds to the level of several notches in the SE crater wall. Throughout the short historical period beginning in 1826 the volcano has had long periods of continuous hydrothermal activity and steam release, punctuated by small-to-medium eruptions. Its activity also forms a prominent part of Maori legends. The most recent eruptive episode, which began on 7 March 2000, included the largest eruption at White Island in the past 20 years on 27 July.

Source: GVP