Volcanos

Roundup of Global Volcanic Activity – Ongoing Activity for the week of 18 April - 24 April 2018

Agung | Bali (Indonesia) : PVMBG reported that although there were often foggy conditions during 18-24 April, white plumes were observed rising as high as 300 m above Agung’s crater rim and drifting E. The Alert Level remained at 3 (on a scale of 1-4) and the exclusion zone continued at a 4-km radius.

Aira | Kyushu (Japan) : JMA reported that there were eight events and 13 explosions at Minamidake crater (at Aira Caldera’s Sakurajima volcano) during 16-23 April. Tephra was ejected as far as 1.1 km from the crater, and plumes rose as high as 2.5 km above the crater rim. At 0038 on 22 April an explosion produced an ash plume that rose 3.3 km and ejected tephra as far as 1.3 km. Crater incandescence was visible on most nights. The Alert Level remained at 3 (on a 5-level scale).

Ambae | Vanuatu : Vanuatu Geohazards Observatory (VGO) reported that during April the eruption from a cone in Ambae’s Lake Voui continued through 23 April, with ash emissions and some lava fountaining. Ash, scoria, and acid rain fell on the island. Observations on 21 April confirmed that the cone had grown, and that the crater in the center of the cone was larger; a small lake was present in the crater. The Alert Level remained at 3 (on a scale of 0-5), and the report reminded residents to stay at least 3 km away from the active crater.

Ambrym | Vanuatu : On 25 April the Vanuatu Geohazards Observatory (VGO) reported that the lava lakes in Ambrym’s Benbow and Marum craters continued to be active, and produced gas-and-steam emissions. The Alert Level remained at 2 (on a scale of 0-5); the report reminded the public to stay outside of the Permanent Danger Zone defined as a 1-km radius from Benbow Crater and a 2.7-km radius from Marum Crater.

Dukono | Halmahera (Indonesia) : Based on analyses of satellite imagery, wind model data, and notices from PVMBG, the Darwin VAAC reported that during 19-24 April ash plumes from Dukono rose to an altitude of 2.1 km (7,000 ft) a.s.l. and drifted in multiple directions.

Ebeko | Paramushir Island (Russia) : Volcanologists in Severo-Kurilsk (Paramushir Island), about 7 km E of Ebeko, observed explosions during 15 and 17-19 April that sent ash plumes as high as 2.6 km (8,500 ft) a.s.l. The Aviation colour Code remained at Orange (the second highest level on a four-colour scale).

Karymsky | Eastern Kamchatka (Russia) : KVERT reported that the last explosive event at Karymsky occurred on 27 January, and the last thermal anomaly was detected on 26 March. The Aviation colour Code was lowered to Yellow (the second lowest level on a four-colour scale).

Kuchinoerabujima | Ryukyu Islands (Japan) : JMA reported that a low-temperature thermal anomaly persisted near the W fracture in Kuchinoerabujima Shindake crater. In addition, both the number of volcanic earthquakes (generally occurring in a large quantity) and sulfur dioxide flux remained above baselines levels in August 2014. No eruptions have occurred since 19 June 2015, and deflation had been recorded since January 2016; the Alert Level was lowered to 3 (on a scale of 1-5).

Mayon | Luzon (Philippines) : PHIVOLCS reported that during 18-24 April white steam plumes from Mayon drifted NW, W, SW, and NE. Crater incandescence was visible at night. The sulfur dioxide flux was 796 tonnes/day on 17 April. The Alert Level remained at 2 (on a 0-5 scale) and PHIVOLCS reminded residents to stay away from the 6-km-radius Permanent Danger Zone and the 7-km Extended Danger Zone on the SSW and ENE flanks.

Pacaya | Guatemala : INSIVUMEH reported increased activity at Pacaya’s Mackenney Crater during 18-19 April. Strombolian explosions ejected material as high as 50 m above the crater rim, and four lava flows traveled 200-500 m down the SW, W, and NW flanks. Strombolian explosions continued to be detected during 21-23 April.

Sabancaya | Peru : Observatorio Vulcanológico del Sur del IGP (OVS-IGP) and Observatorio Vulcanológico del INGEMMET (OVI) reported that explosive activity at Sabancaya increased compared to the previous week; explosions averaged 19 per day during 16-22 April. Seismicity was dominated by long-period events, with a rise in signals indicating emissions. Gas-and-ash plumes rose as high as 2.2 km above the crater rim and drifted 40 km NW, W, and SW. The MIROVA system detected five thermal anomalies, and on 17 April the sulfur dioxide gas flux was high at 3,421 tons/day. The report noted that the public should not approach the crater within a 12-km radius.

Sheveluch | Central Kamchatka (Russia) : KVERT reported that a weak thermal anomaly over Sheveluch was identified in satellite images during 14-18 April. The Aviation colour Code remained at Orange.