Volcanos

Roundup of Global Volcanic Activity – Ongoing Activity for the week of 20 June – 26 June 2018

Aira | Kyushu (Japan) : JMA reported that there were four events and one explosion at Minamidake crater (at Aira Caldera’s Sakurajima volcano) during 18-25 June, with ash plumes rising as high as 1.9 km above the crater rim. Crater incandescence was visible at night on 18 June. The Alert Level remained at 3 (on a 5-level scale).

Cleveland | Chuginadak Island (USA) : AVO reported that a satellite image of Cleveland acquired on 25 June showed a small, circular lava flow about 80 m in diameter in the summit crater. The presence of a flow over the active vent increases the chances of an explosion, so AVO raised the Aviation colour Code to Orange and the Volcano Alert Level to Watch.

Copahue | Central Chile-Argentina border : The Buenos Aires VAAC reported that on 24 June diffuse steam emissions with possible ash were visible in webcam views rising to an altitude of 3.6 km (12,000 ft) a.s.l.

Dukono | Halmahera (Indonesia) : Based on PVMBG observations and satellite data, the Darwin VAAC reported that during 20-26 June ash plumes from Dukono rose to altitudes of 1.8-2.1 km (6,000-7,000 ft) a.s.l. and drifted NW, W, and SW.

Ebeko | Paramushir Island (Russia) : KVERT reported that on 15 June an ash plume from Ebeko was visible in satellite images drifting 14 km SE. Video data from SVERT and KBGS RAS (Kamchatka Branch, Geophysical Service, Russian Academy of Sciences) showed ash explosions during 17-18 June that sent ash plumes to 2.5-3 km (8,200-10,000 ft) a.s.l. The Aviation colour Code remained at Orange (the second highest level on a four-colour scale).

Fuego | Guatemala : INSIVUMEH and CONRED reported that during 20-26 June multiple lahars at Fuego were often hot, steaming, and had a sulfur odor, and were generated from heavy rains and the recent accumulation of pyroclastic-flow deposits from the 3 June events. Lahars remained a significant hazard, and descended the Cenizas (SSW), Las Lajas (SE), Santa Teresa (W), and Taniluyá (SW) drainages. They were 25-45 m wide, as deep as 3 m, and often carried blocks up to 3 m in diameter, tree trunks, and branches. The agencies warned that because the Las Lajas drainage is full of deposits, lahars can continue to descend that drainage or create new channels in San Miguel Los Lotes (one of the hardest-hit areas).

Explosions continued, producing ash plumes that rose as high as 1.3 km above the crater and drifted as far as 15 km in multiple directions. Ashfall was reported in Panimache, Morelia, Sangre de Cristo, and finca Palo Verde on 22 June. Avalanches of material descended the SE, S, and W flanks (Santa Teresa, Las Lajas, and Cenizas drainages). According to CONRED, as of 26 June, the number of people confirmed to have died due to the 3 June pyroclastic flows was 112, and 197 more were missing. In addition, 12,823 remained evacuated.

Kilauea | Hawaiian Islands (USA) : HVO reported that the eruption at Kilauea’s Lower East Rift Zone (LERZ) and at Halema`uma`u Crater continued during 20-26 June. 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 where the fast-moving flow entered the ocean in the area of the former Kapoho Bay. Fissure 16/18 was often incandescent, and lava effusion was visible at Fissure 6 on 21 June. Fissure 22 produced weak lava fountains on 22 June, and weak spattering and small lava flows on 26 June.

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. Steam plumes rose from areas in the crater as well as from circumferential cracks adjacent to the crater. Explosions from collapse events occurred daily, producing gas-and-ash-poor plumes that rose less than 1.8 km (6,000 ft) a.s.l. and drifted SW. On 24 June HVO noted that since late May these plumes rarely rose higher than 3 km (10,000 ft) a.s.l. where they can cause an aviation hazard; the Aviation colour Code was reduced to Orange.

Fountaining at Fissure 8 continued; lava fountains rose occasionally higher than the 55-m-high spatter cone. Pele's hair and other volcanic glass from the fountaining fell within Leilani Estates. The fountains continued to feed the fast-moving lava flow that traveled NE, and then SE around Kapoho Crater, and into the ocean. Occasional overflows sent small flows down the sides of the channel. The lava-flow front at the ocean was almost 3.2 km wide by 25 June, with lava entering the ocean on the S side of the flow front mainly through an open channel, but also along a 1-km-long area marked with billowing laze plumes.

Kirishimayama | Kyushu (Japan) : JMA reported that at Shinmoedake (Shinmoe peak), a stratovolcano of the Kirishimayama volcano group, an explosive eruption at 0909 on 22 June generated an ash plume that rose 2.6 km above the crater rim and drifted E. Tephra was ejected 1.1 km away, and shock waves were felt in the Miyazaki region. Minor amounts of ash fell in Kirishima prefecture and Kagoshima prefecture to the S, Miyakonojo city (Miyazaki prefecture) to the E, and Takahara Town. The Alert Level remained at 3 (on a scale of 1-5).

Klyuchevskoy | Central Kamchatka (Russia) : KVERT reported that a weak thermal anomaly over Klyuchevskoy was identified in satellite images during 16-17 and 19 June. The Aviation colour Code remained at Orange (the second highest level on a four-colour scale).

Langila | New Britain (Papua New Guinea) : Based on analyses of satellite imagery and model data, the Darwin VAAC reported that during 20-21 June ash plumes from Langila rose to an altitude of 2.4 km (8,000 ft) a.s.l. and drifted W and NW.

Mauna Loa | Hawaiian Islands (USA) : On 21 June HVO reported that seismicity and deformation at Mauna Loa had been at near-background levels for at least the previous six months. The Aviation colour Code was lowered to Green and the Volcano Alert Level was lowered to Normal. During 2014 through most of 2017 seismicity was variable but elevated, and ground deformation was consistent with an influx of magma in the shallow reservoir.

Nishinoshima | Japan : JMA reported that seismic, thermal, RADAR, and sulfur dioxide data all showed no eruptive activity at Nishinoshima since mid-August 2017. During an overflight on 14 June the Japan Coast Guard noted white fumarolic plumes rising about 20 m from the E side of main cone’s inner wall and from the center of the crater. Ocean water all around the island was discoloured, especially in the N-to-NW quadrant where the yellowish brown water extended 200-300 m from the shore. On 20 June the JMA reduced the warning level for the island, specifying hazards were less severe “around the crater” (encompassing areas within 500 m).

Sabancaya | Peru : Observatorio Vulcanológico del Sur del IGP (OVS-IGP) and Observatorio Vulcanológico del INGEMMET (OVI) reported that explosions at Sabancaya averaged 29 per day during 18-24 June. Hybrid earthquakes were infrequent and low magnitude. Gas-and-ash plumes rose as high as 1.8 km above the crater rim and drifted 30 km S, SE, and E. The MIROVA system detected 11 thermal anomalies, and on 21 June the sulfur dioxide gas flux was high at 4,900 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 16-17 and 19 June. The Aviation colour Code remained at Orange (the second highest level on a four-colour scale).

Sinabung | Indonesia : Based on observations by PVMBG, satellite and webcam images, and model data, the Darwin VAAC reported that during 20-22 June ash plumes from Sinabung rose 3-3.7 km (10,000-12,000 ft) a.s.l. and drifted SE and E. The Alert Level remained at 4 (on a scale of 1-4), with a general exclusion zone of 3 km and extensions of 7 km on the SSE sector, 6 km in the ESE sector, and 4 km in the NNE sector.

Yasur | Vanuatu : Based on webcam images and local visual observations the Wellington VAAC reported that during 20-21 June intermittent, low-level ash plumes from Yasur rose to an altitude of 1.5 km (5,000 ft) a.s.l. and drifted SE.