Volcanos

Roundup of Global Volcanic Activity – Ongoing Activity for the week of 4 July – 10 July 2018

Aira | Kyushu (Japan) : JMA reported that there were two events and three explosions at Minamidake crater (at Aira Caldera’s Sakurajima volcano) during 2-9 July, with ash plumes rising as high as 1.3 km above the crater rim and material ejected as far as 1.1 km. Crater incandescence was sometimes visible at night. The Alert Level remained at 3 (on a 5-level scale).

Cleveland | Chuginadak Island (USA) : AVO reported that unrest at Cleveland continued during 4-10 July, though nothing significant was detected in seismic or infrasound data. Meteorological cloud cover often prevented views of the crater. Weakly elevated surface temperatures were identified in satellite images during 7 and 9-10 July; a small steam cloud was visible on 7 July. 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 4-10 July ash plumes from Dukono rose to altitudes of 1.5-2.1 km (5,000-7,000 ft) a.s.l. and drifted N, NE, and E.

Ebeko | Paramushir Island (Russia) : Volcanologists in Severo-Kurilsk (Paramushir Island), about 7 km E of Ebeko, observed explosions during 30 June-1 July that sent ash plumes as high as 3.2 km (10,500 ft) a.s.l. Satellite data showed ash plumes drifting 57 km SE on 1 July. The Aviation colour Code remained at Orange (the second highest level on a four-colour scale).

Fuego | Guatemala : INSIVUMEH and CONRED reported relatively quiet conditions at Fuego during 4-9 July characterized mainly by gas emissions and block avalanches on the flanks. During 7-8 July there was about one explosion detected every two hours, producing diffuse ash plumes that rose 500 m above the crater and drifted SW. Block avalanches descended the Seca (W), Cenizas (SSW), and Las Lajas (SE) drainages, while lahars were present in the El Jute (SE), Las Lajas, Cenizas, Taniluyá (SW), Seca, Mineral, and Pantaleón (W) drainages. Seismicity increased on 10 July. Explosions generated ash plumes that rose 2.3 km and drifted 12 km SE, causing ashfall in Morelia (9 km SW) and Panimaché (8 km SW). According to CONRED, as of 4 July, the number of people confirmed to have died due to the 3 June pyroclastic flows was 113, and 332 remained missing.

Kilauea | Hawaiian Islands (USA) : HVO reported that the eruption at Kilauea’s Lower East Rift Zone (LERZ) and at Overlook Crater within Halema`uma`u Crater continued during 4-10 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. Fissure 22 produced spattering 50-80 m above its spatter cone and fed short lava flows that traveled NE on 4 July; weak spattering was visible form the cone the rest of the week.

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, producing gas-and-ash-poor plumes.

Fountaining at Fissure 8 continued; lava fountains rarely rose 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 lava flow that traveled NE, and then SE around Kapoho Crater. Occasional overflows sent small flows down the sides of the channel that did not extend beyond areas previously covered in lava in the upper part of the channel; overflows further down traveled beyond the flow-field boundary. Small brush fires were ignited from some of the overflows. A thermal map from 6 July showed that lava was not entering the ocean from the main channel and that the open channel ended about 2 km inland. Lava was flowing into the ocean at the N part of the broad flow front. Observations on 9 July indicated that a blockage had formed upstream of Kapoho Crater, and by 10 July a small lobe was moving around the W side of the crater.

Pacaya | Guatemala : INSIVUMEH reported that during 5-10 July Strombolian explosions at Pacaya’s Mackenney Crater ejected material as high as 30 m above the crater rim. White gas plumes drifted SW. A lava flow originating from Mackenney Crater traveled 500 m down the N flank during 7-8 July, reaching the volcano’s base.

Sabancaya | Peru : Observatorio Vulcanológico del Sur del IGP (OVS-IGP) and Observatorio Vulcanológico del INGEMMET (OVI) reported that explosions at Sabancaya averaged 22 per day during 2-8 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 nine thermal anomalies, and on 3 July the sulfur dioxide gas flux was high at 4,715 tons/day. The report noted that the public should not approach the crater within a 12-km radius.

Santa Maria | Guatemala : INSIVUMEH reported that during 5-10 July explosions at Santa María's Santiaguito lava-dome complex generated ash plumes that rose 200-700 m and drifted SW and W. Local ashfall was reported. Avalanches of material descended the SE and W flanks of the lava dome.

Sheveluch | Central Kamchatka (Russia) : KVERT reported that a weak thermal anomaly over Sheveluch was identified in satellite images during 4-5 July. The Aviation colour Code remained at Orange (the second highest level on a four-colour scale).