Volcanos

Roundup of Global Volcanic Activity – Ongoing Activity for the Week 11 March 2020 – 17 March 2020

Aira | Kyushu (Japan) : JMA reported that during 9-16 March incandescence from Minamidake Crater (at Aira Caldera’s Sakurajima volcano) was visible nightly. Occasional eruptive events were recorded. An eruption at 1433 on 12 March generated an ash plume that rose 2.1 km above the crater rim. The Alert Level remained at 2 (on a 5-level scale).

Asosan | Kyushu (Japan) : JMA reported that eruptive activity at Asosan was recorded during 9-16 March. Gray-to-white ash plumes rose 600-800 m above the crater rim and caused ashfall in areas downwind. The sulfur dioxide emission rate was high at 1,600-1,700 tons per day on 11 and 16 March. The Alert Level remained at 2 (on a scale of 1-5).

Dukono | Halmahera (Indonesia) : Based on satellite and wind model data, the Darwin VAAC reported that during 11-17 March ash plumes from Dukono rose to 2.1 km (7,000 ft) a.s.l. and drifted in multiple directions. 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.

Ebeko | Paramushir Island (Russia) : Volcanologists in Severo-Kurilsk (Paramushir Island), about 7 km E of Ebeko, observed explosions on 8 March that sent ash plumes up to 2.5 km (8,200 ft) a.s.l. Ash plumes drifted NE. The Aviation colour Code remained at Orange (the second highest level on a four-colour scale).

Ibu | Halmahera (Indonesia) : The Darwin VAAC reported that on 17 March multiple discrete ash plumes from Ibu rose to 2.1 km (7,000 ft) a.s.l. and drifted SW based on satellite images and weather models. The Alert Level remained at 2 (on a scale of 1-4), and the public was warned to stay at least 2 km away from the active crater, and 3.5 km away on the N side.

Kadovar | Papua New Guinea : Based on satellite and wind model data, the Darwin VAAC reported that during 13-15 March ash plumes from Kadovar rose to an altitude of 1.5 km (5,000 ft) a.s.l. and drifted SE.

Kerinci | Indonesia : PVMBG reported that at 1633 on 14 March a brown ash emission rose 500 m above Kerinci’s summit and drifted WNW. The Alert Level remained at 2 (on a scale of 1-4), and the public was warned to remain outside of the 3-km exclusion zone.

Klyuchevskoy | Central Kamchatka (Russia) : KVERT reported that Strombolian activity at Klyuchevskoy was visible during 6-13 March, and the number of hot avalanches descending the flanks in all directions significantly increased. A bright thermal anomaly was identified daily in satellite images, and gas-and-steam plume containing some ash drifted 135 km E, NE, and N during 8-9 and 12 March. The Aviation colour Code remained at Orange.

Nevado del Ruiz | Colombia : Servicio Geológico Colombiano (SGC) reported that three gas-and-ash emissions from Nevado del Ruiz recorded on 10 March (at 0742, 1029, and 1055) rose 345-700 m above the summit and drifted SW, S, and SE. Minor ashfall was reported around the volcano and in towns downwind. The Alert Level remained at 3 (Yellow; the second lowest level on a four-colour scale).

Nevados de Chillan | Chile : SERNAGEOMIN lowered the Alert Level for Nevados de Chillán to Yellow, the second lowest level on a four-colour scale, on 5 March. ONEMI maintained an Alert Level Yellow (the middle level on a three-colour 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.

Nishinoshima | Japan : During an overflight on 9 March the Japan Coast Guard (JCG) noted continuous activity from the central vent at Nishinoshima, including an ash plume rising as high as 1 km. Ejected material landed near the cone’s base. Lava from the NE side of the central vent flowed 1 km N and into the sea. Steam plumes rose along the E coast where lava entered the sea. Lava also effused from a vent on the SW flank of the cone. Discoloured yellow-green water was visible offshore to the W, N, and E. Sulfur dioxide emissions had increased since 17 February measurements. The marine exclusion zone was defined as a radius of about 2.6 km from the island.

Reykjanes | Iceland : On 18 March IMO raised the Aviation colour Code for Reykjanes to Yellow noting that recent InSAR and GPS data indicated that during the second week of March deformation had restarted. The uplift was concentrated in the same place as that recorded in January-February, though at a slower rate. The cause of the deformation was likely an intrusion of magma at 4.5 km depth. A large (M 4.6) earthquake was recorded on 12 March and located 3.5 km NE of Thorbjorn, possibly connected to the inflation. A sequence of aftershocks lasted for a few days and was characterized by eight earthquakes over M 3 and about 80 events with magnitudes between 2 and 3. Since the large event a total of 850 earthquakes were recorded in the area.

Rincon de la Vieja | Costa Rica : OVSICORI-UNA reported a minor increase in tremor amplitude at Rincón de la Vieja beginning at 0200 on 12 March. At 1845 on 14 March an eruption was recorded by the seismic network, but weather conditions prevented visual confirmation; strong tremor was recorded during 1845-2030. Tremor levels increased at around 0300 on 15 March and stopped around 0100 on 17 March, possibly indicating a small eruption.

Semisopochnoi | United States : Seismicity at Semisopochnoi increased over a period of a few days and by 15 March was characterized by nearly continuous tremor and frequent signals indicating small explosions. The unrest prompted AVO to raise the Aviation colour Code to Orange and the Volcano Alert Level to Watch on 15 March. A robust steam plume rising from the N cone of Mount Cerberus and minor ash deposits around the crater rim were visible in a clear satellite image acquired on 16 March.

Sheveluch | Central Kamchatka (Russia) : KVERT reported that a thermal anomaly over Sheveluch was identified in satellite images during 6-13 March. The Aviation colour Code remained at Orange (the second highest level on a four-colour scale).

Shishaldin | Fox Islands (USA) : Lava and a possible new cone in Shishaldin’s summit crater were visible in a satellite image on 14 March prompting AVO to raise the Volcano Alert Level to Watch and the Aviation colour Code to Orange. Weak but elevated seismicity was also recorded along with small explosion signals during 14-17 March. Elevated surface temperatures, consistent with lava in the summit crater, were identified in satellite images during 15-17 March. A small steam plume rising from the summit crater was visible in a webcam image on 17 March.

Suwanosejima | Ryukyu Islands (Japan) : JMA reported that during 28 February-6 March incandescence from Suwanosejima’s Ontake Crater was visible nightly. Occasional eruptive events generated ash plumes that rose as high as 900 m above the crater rim. The Alert Level remained at 2 (on a 5-level scale).

Taal | Luzon (Philippines) : PHIVOLCS reported that during 11-17 March weak steam plumes at Taal rose 50-100 m above Volcano Island lake and drifted SW and NE. According to the Disaster Response Operations Monitoring and Information Center (DROMIC) there were a total of 4,131 people in 11 evacuation centers, and an additional 17,563 displaced people were staying at other locations as of 11 March. The Alert Level remained at 2 (on a scale of 0-5) and PHIVOLCS recommended no entry onto Volcano Island, the area defined as the Permanent Danger Zone.

Yasur | Vanuatu : Based on webcam images and satellite data the Wellington VAAC reported that during on 13 and 17 March low-level ash plumes from Yasur rose to an altitude of 1.5 km (5,000 ft) a.s.l. and drifted N and SE.

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