Roundup of Global Volcanic Activity – Ongoing Activity for the week of 6 June – 12 June 2018
Agung | Bali (Indonesia) : PVMBG reported that during 1 May-7 June activity at Agung remained at a relatively high level. Emissions were mostly water vapor, occasionally with ash. In general, tiltmeter and GPS showed long-term deflation since December 2017, though inflation began to be detected the second week of May; deformation analysis indicated that magma continued to accumulate about 3-4 km below the crater. Low- and high-frequency earthquakes also suggested rising magma. Sulfur dioxide flux was 190-203 tons/day, and thermal anomalies in the crater were identified in satellite data. The erupted volume of lava was estimated to be 23 million cubic meters, equivalent to about a third of the total crater volume. At 2214 on 10 June an event generated an ash plume that drifted W at an unspecified altitude. 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 there were eight events and five explosions at Minamidake crater (at Aira Caldera’s Sakurajima volcano) during 4-11 June. Crater incandescence was occasionally visible at night. Ash plumes rose up to 2 km above the crater rim, except an event at 1135 on 10 June produced a plume that rose 3.5 km. Tephra was ejected as far as 1.3 km from the crater during 8-11 June. The Alert Level remained at 3 (on a 5-level scale).
Ambae | Vanuatu : The Vanuatu Meteorology and Geo-hazards Department reported that activity at Ambae’s Lake Voui decreased in May, and by 7 June had ceased; the Alert Level was lowered to 2 (on a scale of 0-5) and a 2-km-radius exclusion zone was emplaced. Steam and volcanic gas emissions continued, and were reportedly smelled by local residents near the volcano.
Ambrym | Vanuatu : On 7 June the Vanuatu Geohazards Observatory (VGO) reported that the lava lakes in Ambrym’s Benbow and Marum craters continued to be active, and produced sustained and substantial 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.
Cleveland | Chuginadak Island (USA) : AVO reported that low-level unrest at Cleveland continued during 6-12 June. Elevated surface temperatures were identified using satellite data on most days, during times of cloud-free observations. Nothing unusual was observed in seismic or pressure sensor data. Steam emissions were observed during 11-12 June. The Aviation colour Code remained at Yellow and the Volcano Alert Level remained at Advisory.
Dukono | Halmahera (Indonesia) : Based on PVMBG observations and satellite data, the Darwin VAAC reported that during 6-12 June ash plumes from Dukono rose to altitudes of 1.8-2.1 km (6,000-7,000 ft) a.s.l. and drifted W, NW, N, NE, and E.
Ebeko | Paramushir Island (Russia) : KVERT reported that a diffuse ash plume drifting 8 km E of Ebeko was identified in satellite images on 5 June. The Aviation colour Code remained at Orange (the second highest level on a four-colour scale).
Kadovar | Papua New Guinea : According to the Darwin VAAC a pilot observed an ash plume from Kadovar rising to an altitude of 1.2 km (4,000 ft) a.s.l. on 10 June. The ash plume was not identified in satellite data.
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 7-12 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 Kapoho Bay area. Minor lava activity at Fissures 16/18 was occasionally noted.
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; the floor had subsided at least 100 m during the previous few weeks, and by 12 June the lowest point was 300 m below the crater rim. Steam plumes rose from areas in the crater as well as from circumferential cracks adjacent to the crater.
Summit explosions occurred almost daily. Explosions at 1607 and 0244 on 6 and 8 June, respectively, each produced an ash plume that rose 3 km (10,000 ft) a.s.l. An explosion was recorded at 0448 on 9 June. Two explosions, the second larger than the first, were recorded at 0046 and 0443 on 11 June. An ash-poor explosion occurred at 0152 on 12 June. A pattern of an increasing number of earthquakes, an explosion, and then a drop-off of seismicity immediately afterwards had emerged during the past few weeks and continued.
A total of 12 rockfalls in Pu’u ‘O’o Crater were recorded between 1031 and 1056 on 8 June, following a M 3.2 earthquake at the summit. A red dust plume was visible around 1050 but dissipated quickly.
Fountaining at Fissue 8 was stable, though by 10 June three closely spaced fountains were active within the 35-m-high spatter cone. The heights of the fountains varied, but rose no higher than 70 m. 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. The width of the channel varied from 100-300 m along its length. Periodic overflows sometimes sent small flows down the sides of the channel. Lava entered the ocean at Kapoho Bay, building a lava delta that by 11 June was just over 100 hectares in area. A plume of laze rose from the entry points. An area of strong thermal upwelling in the ocean around 920 m out from the visible lava-delta front was visible beginning on 7 June, suggesting lava flowing on the ocean floor. According to a news report, the Hawaii County Mayor noted that by 8 June lava flows had destroyed over 600 homes.
Klyuchevskoy | Central Kamchatka (Russia) : KVERT reported that a thermal anomaly over Klyuchevskoy and a diffuse ash plume drifting 12 km W were identified in satellite images on 6 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 on 7 June a minor ash emission from Langila rose to an altitude of 3.4 km (11,000 ft) a.s.l., slowly drifted SW, and detached form the summit. On 10 June a discrete event produced an ash plume that rose to 2.1 km (7,000 ft) a.s.l. and dissipated.
Pacaya | Guatemala : INSIVUMEH and CONRED reported that on 6 June a lava flow emerged from a vent on La Meseta (the Mesa) on Pacaya’s NW flank and traveled 200 m over a period of six hours. Strombolian explosions ejected material as high as 50 m above the crater rim during 7-10 June.
Popocatepetl | Mexico : CENAPRED reported that each day during 6-12 June there were 19-34 steam-and-gas emissions from Popocatépetl, and nightly crater incandescence. Explosions were detected almost every day: at 2026 on 7 June; 0130 on 8 June; 1756, 1931, and 2358 on 9 June; 1724 on 10 June. An explosion at 0220 on 11 June ejected incandescent fragments. The Alert Level remained at Yellow, Phase Two.
Sangay | Ecuador : The Washington VAAC reported that on 8 June a possible discrete ash emission from Sangay rose to an altitude of 5.8 km (19,000 ft) a.s.l. and drifted 28 km WSW before dissipating.
Sheveluch | Central Kamchatka (Russia) : KVERT reported that a weak thermal anomaly over Sheveluch was identified in satellite images during 5-6 June. The Aviation colour Code remained at Orange (the second highest level on a four-colour scale).