Volcanos

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

Agung | Bali (Indonesia) : PVMBG reported that plumes rose 200-500 m above Agung’s crater rim on 18, 20, and 23 July. Gray plumes rose as high as 1.5 km on 22 July. The Alert Level remained at 3 (on a scale of 1-4) and the exclusion zone was stable at a 4-km radius.

Aira | Kyushu (Japan) : JMA reported that at 1336 on 17 July an event at Minamidake crater (at Aira Caldera’s Sakurajima volcano) produced a plume that rose 1.2 km above the crater rim. Sulfur dioxide emissions were 1,300 tons per day that same day. Occasional small events were recorded during 20-23 July, and crater incandescence was visible on 22 and 23 July. The Alert Level remained at 3 (on a 5-level scale).

Ambae | Vanuatu : Based on satellite data, webcam observations, and wind model data, the Wellington VAAC reported that during 17-24 July ash plumes from the vent at Ambae’s Lake Voui rose to altitudes of 2.1-5.5 km (7,000-18,000 ft) a.s.l. and drifted N, NE, E, and SE. According to news articles, activity intensified on 17 July with significant ashfall impacting the N and E parts of the island, causing dark conditions for residents. Rumbling noises were reported at Penama Provincial Headquarters at Saratamata, more than 30 km away. Volcanologists conducting field work in the areas noted widespread damage and disruption to the local population; roads going to the W part of the island had been washed away.

Bagana | Bougainville (Papua New Guinea) : Based on analyses of satellite imagery and model data, the Darwin VAAC reported that on 22 July an ash plume from Bagana rose to an altitude of 2.4 km (8,000 ft) a.s.l. and drifted W.

Cleveland | Chuginadak Island (USA) : AVO reported that unrest at Cleveland continued during 18-23 July, though nothing significant was detected in seismic or infrasound data. Weakly elevated surface temperatures were identified in satellite images during 18 and 23-24 July; meteorological cloud cover hindered views of the crater on most of the other days. A small deposit of blocks within the summit crater and just below the E crater rim observed only in satellite data suggested the occurrence of a very small explosion undetectable in seismic and pressure sensor data. The Aviation colour Code remained at Orange and the Volcano Alert Level remained at Watch.

Dukono | Halmahera (Indonesia) : Based on PVMBG observations and satellite data, the Darwin VAAC reported that during 18-23 July ash plumes from Dukono rose to an altitude of 1.8 km (6,000 ft) a.s.l. and drifted NW, N, NE, and E.

Ebeko | Paramushir Island (Russia) : Volcanologists in Severo-Kurilsk (Paramushir Island), about 7 km E of Ebeko, observed explosions during 13-20 July that sent ash plumes as high as 3.4 km (11,200 ft) a.s.l. The Aviation colour Code remained at Orange (the second highest level on a four-colour scale).

Fuego | Guatemala : INSIVUMEH reported that during 19-20 and 23-24 July avalanches of material from Fuego’s crater descended the S, SW, and W flanks (Santa Teresa, Las Lajas, El Jute, and Cenizas drainages). Weak explosions during 23-24 July sent low ash plumes N.

Karymsky | Eastern Kamchatka (Russia) : KVERT reported that a thermal anomaly over Karymsky was identified in satellite images during 13-20 July, along with ash plumes that drifted as far as 500 km W and SW during 14-19 July. The Aviation colour Code remained at Orange (the second highest level on a four-colour scale).

Kerinci | Indonesia : Based on satellite data, the Darwin VAAC reported that on 22 July an ash plume from Kerinci rose to an altitude of 4.3 km (14,000 ft) a.s.l. and drifted SW.

Kilauea | Hawaiian Islands (USA) : HVO reported that the eruption at Kilauea’s Lower East Rift Zone (LERZ) and within Halema`uma`u Crater continued during 18-24 July. Lava fountaining and spatter was concentrated at Fissure 8, feeding lava flows that spread through Leilani Estates and Lanipuna Gardens subdivisions, and built out the coastline at multiple ocean entries.

Inward slumping of the crater rim and walls of Halema`uma`u continued, adjusting from the withdrawal of magma and subsidence of the summit area. Explosions from collapse events occurred almost daily, often followed by a surge in activity at Fissure 8. Sulfur dioxide emissions from the summit were very low.

Fountaining at Fissure 8 continued, producing Pele's hair and other volcanic glass that fell within Leilani Estates. The fountains continued to feed the lava flow that traveled NE, and then SSE, W of Kapoho Crater. Channel overflows on 18 July destroyed structures in the Leilani Subdivision. The channelized ‘a’a flow was incandescent along its entire length as it flowed towards the ocean. It generated plumes of laze (a corrosive steam plume mixed with hydrochloric acid and fine volcanic glass particles) at several points along a broad 6-km-wide flow front, though the main entry area was at Ahalanui, a few hundred meters E of the flow edge which was 175 m NE of Isaac Hale Park (by 24 July). HVO noted that the lava delta was unstable as it has been built out as far as 800 m from the original coastline on unconsolidated lava fragments and sand.

Pacaya | Guatemala : INSIVUMEH reported that during 19-20 and 23-24 July Strombolian explosions at Pacaya’s Mackenney Crater ejected material as high as 30 m above the crater rim. A 200-m-long lava flow originating from Mackenney Crater was visible on NW flank.

Sabancaya | Peru : Observatorio Vulcanológico del Sur del IGP (OVS-IGP) and Observatorio Vulcanológico del INGEMMET (OVI) reported that explosions at Sabancaya averaged 25 per day during 16-22 July. Hybrid earthquakes were infrequent and low-magnitude. Gas-and-ash plumes rose as high as 2.5 km above the crater rim and drifted 30 km S, SE, and E. The MIROVA system detected one thermal anomaly, and on 18 July the sulfur dioxide gas flux was very high at 12,068 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 satellite images showed a thermal anomaly over Sheveluch during 13-20 July, and a plume of re-suspended ash drifting 62 km SE on 18 July. The Aviation colour Code remained at Orange (the second highest level on a four-colour scale).

Turrialba | Costa Rica : OVSICORI-UNA reported increased activity at Turrialba during 23-24 July characterized by small sporadic emissions. A very low and diffuse ash plume rose from the crater on 24 July, causing ashfall in Coronado, Tibás (35 km WSW), Goicoechea (28 km WSW), Moravia (31 km WSW), and other areas in the Valle Central.