New activity/unrest was reported for 1 volcano from November 27 to December 3, 2019. Ongoing activity was reported for 15 volcanoes during the same period.
New activity/Unrest: White Island, North Island (New Zealand).
Ongoing Activity: Aira, Kyushu (Japan) | Dukono, Halmahera (Indonesia) | Ebeko, Paramushir Island (Russia) | Etna, Sicily (Italy) | Ibu, Halmahera (Indonesia) | Karangetang, Siau Island (Indonesia) | Klyuchevskoy, Central Kamchatka (Russia) | Krakatau, Indonesia | Nevados de Chillan, Chile | Popocatepetl, Mexico | Sabancaya, Peru | Sangeang Api, Indonesia | Sheveluch, Central Kamchatka (Russia) | Shishaldin, Fox Islands (USA) | Stromboli, Aeolian Islands (Italy).
White Island, North Island (New Zealand)
37.52°S, 177.18°E, Summit elev. 321 m
On 3 December GeoNet reported that unrest at White Island had continued during the previous week. Explosive gas-and-steam-driven fountaining occurred from the active vent area on the W side of the 1978/90 Crater Complex, near the 2012 lava dome, at the back of the crater lake. Mud and debris were ejected 20-30 m above the vent. The Volcanic Alert Level remained at 2 and the Aviation Color Code remained at Yellow.
Geological summary: 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 island consists of two overlapping andesitic-to-dacitic 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. Volckner Rocks, four sea stacks that are remnants of a lava dome, lie 5 km NNE. Intermittent moderate phreatomagmatic and strombolian eruptions have occurred throughout the short historical period beginning in 1826, but its activity also forms a prominent part of Maori legends. Formation of many new vents during the 19th and 20th centuries has produced rapid changes in crater floor topography. Collapse of the crater wall in 1914 produced a debris avalanche that buried buildings and workers at a sulfur-mining project.
Aira, Kyushu (Japan)
31.593°N, 130.657°E, Summit elev. 1117 m
JMA reported that incandescence from Minamidake Crater (at Aira Caldera’s Sakurajima volcano) was visible at night during 25 November-2 December. There were 16 explosions and three non-explosive eruptive events detected by the seismic network. Ash plumes rose as high as 2.7 km above the crater rim and blocks were ejected as far as 1.3 km away. One of the explosions, recorded at 2010 on 28 November, produced an eruption plume that rose 3.3 km. The Alert Level remained at 3 (on a 5-level scale).
Geological 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.
Dukono, Halmahera (Indonesia)
1.693°N, 127.894°E, Summit elev. 1229 m
Based on satellite and wind model data, and information from PVMBG, the Darwin VAAC reported that during 27 November-3 December ash plumes from Dukono rose to an altitude of 2.1 km (7,000 ft) a.s.l. and drifted SE, E, and NE. The Alert Level remained at 2 (on a scale of 1-4), and the public was warned to remain outside of the 2-km exclusion zone.
Geological 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.
Ebeko, Paramushir Island (Russia)
50.686°N, 156.014°E, Summit elev. 1103 m
Volcanologists in Severo-Kurilsk (Paramushir Island), about 7 km E of Ebeko, observed explosions during 22-23 and 28 November that sent ash plumes up to 2.5 km (8,200 ft) a.s.l. Ash plumes drifted SE and E, and produced ashfall in Severo-Kurilsk on 23 November. The Aviation Color Code remained at Orange (the second highest level on a four-color scale).
Geological summary: The flat-topped summit of the central cone of Ebeko volcano, one of the most active in the Kuril Islands, occupies the northern end of Paramushir Island. Three summit craters located along a SSW-NNE line form Ebeko volcano proper, at the northern end of a complex of five volcanic cones. Blocky lava flows extend west from Ebeko and SE from the neighboring Nezametnyi cone. The eastern part of the southern crater contains strong solfataras and a large boiling spring. The central crater is filled by a lake about 20 m deep whose shores are lined with steaming solfataras; the northern crater lies across a narrow, low barrier from the central crater and contains a small, cold crescentic lake. Historical activity, recorded since the late-18th century, has been restricted to small-to-moderate explosive eruptions from the summit craters. Intense fumarolic activity occurs in the summit craters, on the outer flanks of the cone, and in lateral explosion craters.
Etna, Sicily (Italy)
37.748°N, 14.999°E, Summit elev. 3295 m
INGV reported that eruptive activity at Etna’s summit craters continued during 25 November-1 December. Strombolian explosions at Voragine Crater (VOR) occurred at intervals of 5-10 minutes, and many incandescent jets rose above the crater rim. Some explosions created incandescent flashes in emissions rising above the crater rim. A cone which had started forming on the crater floor in mid-September had continued to grow according to observations by field guides. Sporadic ash emissions began at New Southeast Crater (NSEC) on the evening of 30 November, and a single Strombolian explosion was recorded on 1 December. Incandescence from Bocca Nuova Crater was intermittently visible at night.
Geological 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, sometimes simultaneously. Persistent explosive eruptions, sometimes with minor lava emissions, take place from one or more summit craters. 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.
Ibu, Halmahera (Indonesia)
1.488°N, 127.63°E, Summit elev. 1325 m
Based on PVMBG observations and satellite images, the Darwin VAAC reported that on 3 December an ash plume from Ibu rose to 2.1 km (7,000 ft) a.s.l. and drifted NE. A thermal anomaly was visible in satellite images.
Geological summary: The truncated summit of Gunung Ibu stratovolcano along the NW coast of Halmahera Island has large nested summit craters. The inner crater, 1 km wide and 400 m deep, contained several small crater lakes through much of historical time. The outer crater, 1.2 km wide, is breached on the north side, creating a steep-walled valley. A large parasitic cone is located ENE of the summit. A smaller one to the WSW has fed a lava flow down the W flank. A group of maars is located below the N and W flanks. Only a few eruptions have been recorded in historical time, the first a small explosive eruption from the summit crater in 1911. An eruption producing a lava dome that eventually covered much of the floor of the inner summit crater began in December 1998.
Karangetang, Siau Island (Indonesia)
2.781°N, 125.407°E, Summit elev. 1797 m
PVMBG reported that during 25 November-1 December lava continued to effuse from Karangetang’s Main Crater (S), traveling as far as 1.8 km down the Nanitu, Pangi, and Sense drainages on the SW and W flanks. Sometimes dense white plumes rose to 500 m above the summit. Incandescence from both summit craters was visible at night. The Alert Level remained at 2 (on a scale of 1-4).
Geological summary: Karangetang (Api Siau) volcano lies at the northern end of the island of Siau, about 125 km NNE of the NE-most point of Sulawesi island. The stratovolcano contains five summit craters along a N-S line. It is one of Indonesia's most active volcanoes, with more than 40 eruptions recorded since 1675 and many additional small eruptions that were not documented in the historical record (Catalog of Active Volcanoes of the World: Neumann van Padang, 1951). Twentieth-century eruptions have included frequent explosive activity sometimes accompanied by pyroclastic flows and lahars. Lava dome growth has occurred in the summit craters; collapse of lava flow fronts have produced pyroclastic flows.
Klyuchevskoy, Central Kamchatka (Russia)
56.056°N, 160.642°E, Summit elev. 4754 m
KVERT reported that Strombolian activity at Klyuchevskoy was visible during 21 and 26-27 November, and a weak thermal anomaly was identified in satellite images during 21-25 and 28 November. The Aviation Color Code remained at Orange.
Geological 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.
6.102°S, 105.423°E, Summit elev. 155 m
PVMBG reported that at 0543 on 27 October an eruptive event at Anak Krakatau ejected a white-and-black plume 150 m above the active vent. The Alert Level remained at 2 (on a scale of 1-4), and the public was warned to remain outside of the 2-km-radius hazard zone from the crater.
Geological summary: The renowned volcano Krakatau (frequently misstated as Krakatoa) lies in the Sunda Strait between Java and Sumatra. Collapse of the ancestral Krakatau edifice, perhaps in 416 or 535 CE, formed a 7-km-wide caldera. Remnants of this ancestral volcano are preserved in Verlaten and Lang Islands; subsequently Rakata, Danan, and Perbuwatan volcanoes were formed, coalescing to create the pre-1883 Krakatau Island. Caldera collapse during the catastrophic 1883 eruption destroyed Danan and Perbuwatan, and left only a remnant of Rakata. This eruption, the 2nd largest in Indonesia during historical time, caused more than 36,000 fatalities, most as a result of devastating tsunamis that swept the adjacent coastlines of Sumatra and Java. Pyroclastic surges traveled 40 km across the Sunda Strait and reached the Sumatra coast. After a quiescence of less than a half century, the post-collapse cone of Anak Krakatau (Child of Krakatau) was constructed within the 1883 caldera at a point between the former cones of Danan and Perbuwatan. Anak Krakatau has been the site of frequent eruptions since 1927.
Nevados de Chillan, Chile
36.868°S, 71.378°W, Summit elev. 3180 m
SERNAGEOMIN reported that during 26 November-3 December white-to-gray plumes from Nevados de Chillán’s Nicanor Crater rose as high as 1.7 km above the rim and drifted SE, NE, and NNW. Occasional explosions ejecting incandescent material onto the flank were visible at night. The report noted that the newest lava flow (L4) traveled down the NNE flank adjacent to three previous flows (L1, L2, and L3). The point of emission of L4 was about 60 m SSE of the emission point for the previous three lava flows. L4 had two lobes and was about 90 m long, measured from the rim of Nicanor Crater, on 27 November. By 29 November it had lengthened to 165 m. The volcano Alert Level remained at Orange, the second highest level on a four-color scale. ONEMI maintained an Alert Level Yellow (the middle level on a three-color scale) for the communities of Pinto, Coihueco, and San Fabián, and stated that the public should stay at least 3 km away from the crater on the SW flank and 5 km away on the ENE flank.
Geological summary: The compound volcano of Nevados de Chillán is one of the most active of the Central Andes. Three late-Pleistocene to Holocene stratovolcanoes were constructed along a NNW-SSE line within three nested Pleistocene calderas, which produced ignimbrite sheets extending more than 100 km into the Central Depression of Chile. The largest stratovolcano, dominantly andesitic, Cerro Blanco (Volcán Nevado), is located at the NW end of the group. Volcán Viejo (Volcán Chillán), which was the main active vent during the 17th-19th centuries, occupies the SE end. The new Volcán Nuevo lava-dome complex formed between 1906 and 1945 between the two volcanoes and grew to exceed Volcán Viejo in elevation. The Volcán Arrau dome complex was constructed SE of Volcán Nuevo between 1973 and 1986 and eventually exceeded its height.
19.023°N, 98.622°W, Summit elev. 5393 m
CENAPRED reported that each day during 26 November-3 December there were 124-187 steam-and-gas emissions from Popocatépetl, some of which contained ash through 1 December. An explosion was recorded at 1036 on 26 November. Another explosion at 0233 on 28 November produced an ash plume that rose 1 km above the crater rim and drifted NW. The event also ejected incandescent material onto the flanks as far away as 1.5 km from the crater. The Alert Level remained at Yellow, Phase Two (middle level on a three-color scale).
Geological summary: Volcán Popocatépetl, whose name is the Aztec word for smoking mountain, rises 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 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 Pre-Columbian time.
15.787°S, 71.857°W, Summit elev. 5960 m
Instituto Geofísico del Perú (IGP) reported that an average of 17 daily low-to-medium intensity explosions occurred at Sabancaya during 25 November-1 December. Gas-and-ash plumes rose as high as 4 km above the summit and drifted NE, E, and S. There were five thermal anomalies identified in satellite data, originating from the 240-m-diameter lava dome in the summit crater. The Alert Level remained at Orange (the second highest level on a four-color scale) and the public were warned to stay outside of a 12-km radius.
Geological summary: Sabancaya, located in the saddle NE of Ampato and SE of Hualca Hualca volcanoes, is the youngest of these volcanic centers and the only one to have erupted in historical time. The oldest of the three, Nevado Hualca Hualca, is of probable late-Pliocene to early Pleistocene age. The name Sabancaya (meaning "tongue of fire" in the Quechua language) first appeared in records in 1595 CE, suggesting activity prior to that date. Holocene activity has consisted of Plinian eruptions followed by emission of voluminous andesitic and dacitic lava flows, which form an extensive apron around the volcano on all sides but the south. Records of historical eruptions date back to 1750.
Sangeang Api, Indonesia
8.2°S, 119.07°E, Summit elev. 1912 m
The Darwin VAAC reported that during 27 November-3 December discrete and short-lived ash emissions from Sangeang Api rose to altitudes of 2.4-3.3 km (8,000-11,000 ft) a.s.l. and drifted NW, W, and SW. A thermal anomaly was visible on 27 November. The Alert Level remained at 2 (on a scale of 1-4).
Geological summary: Sangeang Api volcano, one of the most active in the Lesser Sunda Islands, forms a small 13-km-wide island off the NE coast of Sumbawa Island. Two large trachybasaltic-to-tranchyandesitic volcanic cones, Doro Api and Doro Mantoi, were constructed in the center and on the eastern rim, respectively, of an older, largely obscured caldera. Flank vents occur on the south side of Doro Mantoi and near the northern coast. Intermittent historical eruptions have been recorded since 1512, most of them during in the 20th century.
Sheveluch, Central Kamchatka (Russia)
56.653°N, 161.36°E, Summit elev. 3283 m
KVERT reported that a thermal anomaly over Sheveluch was identified in satellite images during 22-29 November. The Aviation Color Code remained at Orange (the second highest level on a four-color scale).
Geological summary: The high, isolated massif of Sheveluch volcano (also spelled Shiveluch) rises above the lowlands NNE of the Kliuchevskaya volcano group. The 1300 km3 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 seismic levels at Shishaldin were variable but elevated during 26 November-3 December. Weather clouds sometimes obscured satellite image views and mostly prevented webcam views, though elevated surface temperatures were still visible in multiple satellite images. An active 1.5-km-long lava flow on the NW flank was visible in satellite images on 1 December. Continuous tremor transitioned to episodic bursts during the morning of 2 December, but by 3 December a decrease in seismic activity and surface temperatures suggested another pause in lava effusion. The Aviation Color Code remained at Orange and the Volcano Alert Level remained at Watch.
Geological 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.
Stromboli, Aeolian Islands (Italy)
38.789°N, 15.213°E, Summit elev. 924 m
INGV reported that during 25 November-1 December activity at Stromboli was characterized by ongoing explosive activity mainly from three vents in Area N (north crater area) and at least three vents in Area C-S (south central crater area). Low-to-medium-intensity explosions from Area N occurred at a rate of 7-11 events per hour and ejected lapilli and bombs 80-150 m above the vents. Ejected tephra fell onto the flanks and some blocks rolled a few hundred meters along the Sciara del Fuoco. Medium-intensity explosions from Area C-S occurred at a rate of 4-8 events per hour and ejected coarse material to heights less than150 m above the vents. Material was deposited along the upper parts of the Sciara del Fuoco.
Geological summary: Spectacular incandescent nighttime explosions at this volcano have long attracted visitors to the "Lighthouse of the Mediterranean." Stromboli, the NE-most of the Aeolian Islands, has lent its name to the frequent mild explosive activity that has characterized its eruptions throughout much of historical time. The small island is the emergent summit of a volcano that grew in two main eruptive cycles, the last of which formed the western portion of the island. The Neostromboli eruptive period took place between about 13,000 and 5,000 years ago. The active summit vents are located at the head of the Sciara del Fuoco, a prominent horseshoe-shaped scarp formed about 5,000 years ago due to a series of slope failures that extend to below sea level. The modern volcano has been constructed within this scarp, which funnels pyroclastic ejecta and lava flows to the NW. Essentially continuous mild Strombolian explosions, sometimes accompanied by lava flows, have been recorded for more than a millennium.