New activity/unrest was observed at 5 volcanoes from November 25 - December 1, 2015. During the same period, ongoing activity was reported for 10 volcanoes.
New activity/unrest: Fuego, Guatemala | Kanlaon, Philippines | Momotombo, Nicaragua | Telica, Nicaragua | Zhupanovsky, Eastern Kamchatka (Russia).
Ongoing activity: Colima, Mexico | Copahue, Central Chile-Argentina border | Cotopaxi, Ecuador | Dukono, Halmahera (Indonesia) | Karymsky, Eastern Kamchatka (Russia) | Kilauea, Hawaiian Islands (USA) | Rinjani, Lombok Island (Indonesia) | Sheveluch, Central Kamchatka (Russia) | Sinabung, Indonesia | Tungurahua, Ecuador.
14.473°N, 90.88°W, Summit elev. 3763 m
INSIVUMEH reported that on 29 November activity at Fuego increased significantly, characterized by large and strong explosions, ash plumes, and lava flows. Ash plumes rose as high as 2.2 km above the crater and drifted 40 km W and SW. Lava fountains rose 500 m above the crater, feeding four lava flows that traveled 3-4 km down the Ceniza, Trinidad, Las Lajas, and Santa Teresa drainages. Ash fell in Panimache I and II (8 km SW), Morelia (9 km SW), Santa Sofía (12 km SW), El Porvenir (8 km ENE), Yucales (12 km SW), Rochelle, Ceylon, and other neighboring communities. Activity declined on 30 November; lava fountains rose 100-150 m, and ash plumes rose 1 km and drifted 25 km WSW. Lava flows were active in five drainages, including the Honda drainage (E flank). On 1 December weak-to-moderate explosions generated ash plumes that rose 400-800 m and drifted 10-12 km W and SW. Lava fountains continued to rise as high as 150 m. The five lava flows were at most 3 km long, and small pyroclastic flows descended the Honda drainage.
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 3763-m-high Fuego and its twin volcano to the north, Acatenango. Construction of Meseta dates back to about 230,000 years and continued until the late Pleistocene or early Holocene. Collapse of Meseta may have produced the massive Escuintla debris-avalanche deposit, which extends about 50 km onto the Pacific coastal plain. Growth of the modern Fuego volcano followed, continuing the southward migration of volcanism that began at Acatenango. In contrast to the mostly andesitic Acatenango, eruptions at Fuego have become more mafic with time, and most historical activity has produced basaltic rocks. Frequent vigorous historical eruptions have been recorded since the onset of the Spanish era in 1524, and have produced major ashfalls, along with occasional pyroclastic flows and lava flows.
10.412°N, 123.132°E, Summit elev. 2435 m
PHIVOLCS reported that the seismic network for Kanlaon detected 11 volcanic earthquakes during 24-25 November. Emissions of gas and ash rose 150 m above the crater and drifted SW on 25 November. The Alert Level remained at 1 (on a scale of 0-5).
Geologic summary: Kanlaon volcano (also spelled Canlaon), the most active of the central Philippines, forms the highest point on the island of Negros. The massive 2435-m-high andesitic stratovolcano is dotted with fissure-controlled pyroclastic cones and craters, many of which are filled by lakes. The largest debris avalanche known in the Philippines traveled 33 km to the SW from Kanlaon. The summit of Kanlaon contains a 2-km-wide, elongated northern caldera with a crater lake and a smaller, but higher, historically active vent, Lugud crater, to the south. Historical eruptions from Kanlaon, recorded since 1866, have typically consisted of phreatic explosions of small-to-moderate size that produce minor ashfalls near the volcano.
12.422°N, 86.54°W, Summit elev. 1297 m
INETER reported that at 0749 on 1 December an explosion at Momotombo generated a gas-and-ash plume that rose 1 km above the crater and drifted SW. Explosions at 0817, 0842, and 0855 generated ash plumes that rose 300 m. Gas emissions were visible the rest of the day. SINAPRED reported that during 1-2 December explosions ejected incandescent tephra and a slow-moving lava flow on the N flank was observed. Ashfall was reported in nearby communities to the W and SW, including La Concha, Los Arcos, Flor de la Piedra, La Paz Centro, and Leóin. Some families in La Paz Centro self-evacuated.
Geologic summary: Momotombo is a young, 1297-m-high stratovolcano that rises prominently above the NW shore of Lake Managua, forming one of Nicaragua's most familiar landmarks. Momotombo began growing about 4500 years ago at the SE end of the Marrabios Range and consists of a somma from an older edifice that is surmounted by a symmetrical younger cone with a 150 x 250 m wide summit crater. Young lava flows from Momotombo have flowed down the NW flank into the 4-km-wide Monte Galán caldera. The youthful cone of Momotombito forms a 391-m-high island offshore in Lake Managua. Momotombo has a long record of strombolian eruptions, punctuated by occasional larger explosive activity. The latest eruption, in 1905, produced a lava flow that traveled from the summit to the lower NE base. A small black plume was seen above the crater after an April 10, 1996 earthquake, but later observations noted no significant changes in the crater. A major geothermal field is located on the southern flank of the volcano.
12.602°N, 86.845°W, Summit elev. 1061 m
INETER reported that four 5-minute-long explosions at Telica were detected at 0602, 0818, 0934, and 1124 on 25 November, and generated ash-and-ash emissions. On 26 November multiple gas-and-ash explosions were detected; the strongest explosion occurred at 0941 and produced an ash plume that rose more than 800 m above the crater. During 26-27 November a total of 29 explosions were detected, with 16 of those producing ash plumes.
Geologic summary: Telica, one of Nicaragua's most active volcanoes, has erupted frequently since the beginning of the Spanish era. This volcano group consists of several interlocking cones and vents with a general NW alignment. Sixteenth-century eruptions were reported at symmetrical Santa Clara volcano at the SW end of the group. However, its eroded and breached crater has been covered by forests throughout historical time, and these eruptions may have originated from Telica, whose upper slopes in contrast are unvegetated. The steep-sided cone of 1061-m-high Telica is truncated by a 700-m-wide double crater; the southern crater, the source of recent eruptions, is 120 m deep. El Liston, immediately SE of Telica, has several nested craters. The fumaroles and boiling mudpots of Hervideros de San Jacinto, SE of Telica, form a prominent geothermal area frequented by tourists, and geothermal exploration has occurred nearby.
Zhupanovsky, Eastern Kamchatka (Russia)
53.589°N, 159.15°E, Summit elev. 2899 m
Based on satellite images, KVERT reported that on 28 November ash plumes from Zhupanovsky rose to altitudes of 5-6 km (16,400-19,700 ft) a.s.l. and drifted 285 km E. The Aviation Color Code was raised to Orange. IVS FED RAS (Institute Volcanology and Seismology Far East Division of the Russian Academy of Sciences) observers noted an ash explosion at 0356 on 1 December; the Tokyo VAAC reported that the resulting ash plume rose to an altitude of 9 km (29,500 ft) a.s.l. and drifted 60 km SE.
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.
19.514°N, 103.62°W, Summit elev. 3850 m
Based on satellite images, wind data, webcam images, and notices from the Mexico City MWO, the Washington VAAC reported that during 24 November-1 December ash plumes from Colima rose to altitudes of 5.2-6.6 km (17,000-22,000 ft) a.s.l. and drifted multiple directions.
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 4320 m high point of the complex) on the north and the 3850-m-high historically active Volcán de Colima at the south. A group of cinder cones of late-Pleistocene age is located on the floor of the Colima graben west and east of the Colima complex. Volcán de Colima (also known as Volcán Fuego) is a youthful stratovolcano constructed within a 5-km-wide caldera, breached to the south, 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.
Copahue, Central Chile-Argentina border
37.856°S, 71.183°W, Summit elev. 2953 m
SERNAGEOMIN reported that during 16-30 November continuous ash emissions from explosions at Copahue's El Agrio crater were recorded by the webcam; plumes rose as high as 1.3 km above the crater on 29 November. Satellite images detected ash plumes drifting as far as 560 km SE and ESE. During an overflight on 28 November scientists observed the absence of the acidic lake and a growing pyroclastic cone. Impact craters from ballistics ejected during minor explosions were within a radius of 300 m of El Agrio. Satellite images detected a thermal anomaly during 28-29 November. The Alert Level remained at Yellow; SERNAGEOMIN recommended no entry into a restricted area within 1.5 km of the crater. ONEMI maintained Level Yellow for the community of Alto Biobío (40 km W) in the Biobío region (since 3 June 2013).
Geologic summary: Volcán Copahue is an elongated composite cone constructed along the Chile-Argentina border within the 6.5 x 8.5 km wide Trapa-Trapa caldera that formed between 0.6 and 0.4 million years ago near the NW margin of the 20 x 15 km Pliocene Caviahue (Del Agrio) caldera. The eastern summit crater, part of a 2-km-long, ENE-WSW line of nine craters, contains a briny, acidic 300-m-wide crater lake (also referred to as El Agrio or Del Agrio) and displays intense fumarolic activity. Acidic hot springs occur below the eastern outlet of the crater lake, contributing to the acidity of the Río Agrio, and another geothermal zone is located within Caviahue caldera about 7 km NE of the summit. Infrequent mild-to-moderate explosive eruptions have been recorded at Copahue since the 18th century. Twentieth-century eruptions from the crater lake have ejected pyroclastic rocks and chilled liquid sulfur fragments.
0.677°S, 78.436°W, Summit elev. 5911 m
IG reported that during 25 November-1 December seismic activity at Cotopaxi was characterized by volcano-tectonic, hybrid, and long-period events. Seismic signals indicating emissions and explosions were also detected. Although cloud cover often prevented observations, gas-and-steam emissions were visible daily. The plumes contained ash on most days and rose as high as 1 km, drifting W and SW. Lahar descended the Agualongo river during 28-29 November and the Mariscal Sucre river on 29 November.
Geologic summary: Symmetrical, glacier-clad Cotopaxi stratovolcano is Ecuador's most well-known volcano and one of its most active. The steep-sided cone is capped by nested summit craters, the largest of which is about 550 x 800 m in diameter. Deep valleys scoured by lahars radiate from the summit of the andesitic volcano, and large andesitic lava flows extend as far as the base of Cotopaxi. The modern conical volcano has been constructed since a major edifice collapse sometime prior to about 5000 years ago. Pyroclastic flows (often confused in historical accounts with lava flows) have accompanied many explosive eruptions of Cotopaxi, and lahars have frequently devastated adjacent valleys. The most violent historical eruptions took place in 1744, 1768, and 1877. Pyroclastic flows descended all sides of the volcano in 1877, and lahars traveled more than 100 km into the Pacific Ocean and western Amazon basin. The last significant eruption of Cotopaxi took place in 1904.
Dukono | Halmahera (Indonesia)
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 25 November-1 December ash plumes from Dukono rose to altitudes of 2.1-2.4 km (7,000-8,000 ft) a.s.l. and drifted 35-165 km in multiple directions.
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 north-flank cone of Gunung Mamuya. This complex volcano presents a broad, low profile with multiple summit peaks and overlapping craters. Malupang Wariang, 1 km SW of the summit crater complex, contains a 700 x 570 m crater that has also been active during historical time.
Karymsky, Eastern Kamchatka (Russia)
54.049°N, 159.443°E, Summit elev. 1513 m
KVERT reported that moderate explosive activity at Karymsky continued during 20-27 November. Satellite images detected a thermal anomaly on 20 November. According to pilot reports, an explosion at 1555 on 30 November generated an ash plume that rose to an altitude of 7.5 km (24,600 ft) a.s.l. and drifted 80 km ESE. 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 during the early Holocene. The caldera cuts the south side of the Pleistocene Dvor volcano and is located outside the north margin of the large mid-Pleistocene Polovinka caldera, which contains the smaller Akademia Nauk and Odnoboky calderas. Most seismicity preceding Karymsky eruptions originated beneath Akademia Nauk caldera, located immediately south. The caldera enclosing Karymsky formed about 7600-7700 radiocarbon years ago; construction of the stratovolcano began about 2000 years later. The latest eruptive period began about 500 years ago, following a 2300-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.
Kilauea, Hawaiian Islands (USA)
19.421°N, 155.287°W, Summit elev. 1222 m
HVO reported that seismicity beneath Kilauea's summit, upper East Rift Zone, and Southwest Rift Zone was at background levels during 25 November-1 December. The lava lake continued to circulate and spatter in the Overlook vent. Webcams recorded multiple incandescent outgassing vents within Pu'u 'O'o; lava flowed from two of the vents on 25 November. The June 27th NE-trending lava flow continued to be active within 6 km NE of Pu'u 'O'o Crater.
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.
Rinjani, Lombok Island (Indonesia)
8.42°S, 116.47°E, Summit elev. 3726 m
Based on satellite and ground observations, the Darwin VAAC reported that during 24-30 November ash plumes from Rinjani rose to altitudes of 3.7-4.3 km (12,000-14,000 ft) a.s.l. and drifted as far as 320 km SW and W.
Geologic summary: Rinjani volcano on the island of Lombok rises to 3726 m, second in height among Indonesian volcanoes only to Sumatra's Kerinci volcano. Rinjani has a steep-sided conical profile when viewed from the east, but the west side of the compound volcano is truncated by the 6 x 8.5 km, oval-shaped Segara Anak (Samalas) caldera. The caldera formed during one of the largest Holocene eruptions globally in 1257 CE, which truncated Samalas stratovolcano. The western half of the caldera contains a 230-m-deep lake whose crescentic form results from growth of the post-caldera cone Barujari at the east end of the caldera. Historical eruptions dating back to 1847 have been restricted to Barujari cone and consist of moderate explosive activity and occasional lava flows that have entered Segara Anak lake.
Sheveluch, Central Kamchatka (Russia)
56.653°N, 161.36°E, Summit elev. 3283 m
KVERT reported that during 20-27 November lava-dome extrusion onto Sheveluch’s N flank was accompanied by fumarolic activity, dome incandescence, ash explosions, and hot avalanches. Satellite images detected a daily thermal anomaly over the dome and SE-drifting ash plumes during 22 and 25-26 November. 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.
3.17°N, 98.392°E, Summit elev. 2460 m
Based on information from PVMBG, the Darwin VAAC reported that on 26 November ash plumes from Sinabung rose to an altitude of 4.3 km (14,000 ft) a.s.l. and drifted SW. On 1 December an ash plume rose to an altitude of 3.4 km (11,000 ft) a.s.l.
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.
1.467°S, 78.442°W, Summit elev. 5023 m
IG reported high seismic activity at Tungurahua during 25 November-1 December, although the number of earthquakes decreased. During periods of clear weather on most days observers noted gas-and-steam plumes rising as high as 1.5 km and drifting mainly W.
Geologic summary: Tungurahua, a steep-sided andesitic-dacitic stratovolcano that towers more than 3 km above its northern base, is one of Ecuador's most active volcanoes. Three major edifices have been sequentially constructed since the mid-Pleistocene over a basement of metamorphic rocks. Tungurahua II was built within the past 14,000 years following the collapse of the initial edifice. Tungurahua II itself collapsed about 3000 years ago and produced a large debris-avalanche deposit and a horseshoe-shaped caldera open to the west, inside which the modern glacier-capped stratovolcano (Tungurahua III) was constructed. Historical eruptions have all originated from the summit crater, accompanied by strong explosions and sometimes by pyroclastic flows and lava flows that reached populated areas at the volcano's base. Prior to a long-term eruption beginning in 1999 that caused the temporary evacuation of the city of Baños at the foot of the volcano, the last major eruption had occurred from 1916 to 1918, although minor activity continued until 1925.