Volcanos

Roundup of Global Volcanic Activity – Ongoing Activity for the week of 1 August - 7 August 2018

Agung | Bali (Indonesia) : PVMBG reported that white plumes rose 100-300 m above Agung’s crater rim during 1 and 2-7 August. The Alert Level remained at 3 (on a scale of 1-4) with the exclusion zone set at a 4-km radius.

Aira | Kyushu (Japan) : JMA reported that there were eight events and seven explosions at Minamidake crater (at Aira Caldera’s Sakurajima volcano) during 30 July-6 August, with ash plumes rising as high as 2.5 km above the crater rim and material ejected as far as 700 m. Crater incandescence was seldom visible at night. Sulfur dioxide emissions were very high at 3,200 tons per day on 2 August. The Alert Level remained at 3 (on a 5-level scale).

Copahue | Central Chile-Argentina border : According to ONEMI, OVDAS-SERNAGEOMIN reported that during 16-31 July there were 107 volcano-tectonic events recorded at Copahue, and 266 earthquakes indicating fluid movement. Webcams recorded gas-and-ash plumes rising from El Agrio crater as high as 1.5 km and nighttime incandescence. The Alert Level remained at Yellow (second highest level on a four-colour scale); SERNAGEOMIN recommended no entry into a restricted area within 1 km of the crater. ONEMI maintained an Alert Level Yellow (the middle level on a three-colour scale) for the municipality of Alto Biobío.

Dukono | Halmahera (Indonesia) : Based on satellite data, wind model data, and notices from PVMBG, the Darwin VAAC reported that during 1 and 3-7 August ash plumes from Dukono rose to altitudes of 1.8-2.1 km (6,000-7,000 ft) a.s.l. and drifted N and NE.

Ebeko | Paramushir Island (Russia) : Volcanologists in Severo-Kurilsk (Paramushir Island), about 7 km E of Ebeko, observed explosions during 29-31 July and on 1 August that sent ash plumes as high as 6 km (19,700 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 a thermal anomaly over Karymsky was identified in satellite images during 27-29 and 31 July, as well as ash plumes drifting 200 km SE, E, and NE during 28-31 July. The Aviation colour Code remained at Orange (the second highest level on a four-colour scale).

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 1-2 August, with lava flowing through the channel and into the ocean producing laze at several points along a broad 2-km-wide flow front at Ahalanui. A few spillovers from the channel set vegetation on fire. By 3 August the lava-flow velocity in the channel was low and on 4 August the output at Fissure 8 had waned. Part of the flow field shifted W about 250 m; the westernmost edge was about 70 m NE of the boat ramp in Isaac Hale Park by 5 August. The lava channel was completely crusted over by 6 August, and a lava lake bubbled in the Fissure 8 cone. The laze plumes at the ocean entry were greatly diminished. During 7-8 August the lava lake in Fissure 8 was 5-10 m below the spillway into the channel. A decreasing number of small active ooze outs near the coast were visible. A collapse event at the summit was recorded at 1155 on 2 August. Seismicity increased afterwards as has been typical since early on in the LERZ eruption, but then decreased along with the rate of deformation. By 7 August deformation had almost stopped. The quiet conditions at the summit represented a significant change from the pattern of seismicity and deformation detected over the past several months.

Sabancaya | Peru : Observatorio Vulcanológico del Sur del IGP (OVS-IGP) and Observatorio Vulcanológico del INGEMMET (OVI) reported that explosions at Sabancaya averaged 19 per day during 30 July-5 August. Hybrid earthquakes were infrequent and low magnitude. Gas-and-ash plumes rose as high as 2.6 km above the crater rim and drifted 30 km SE, E, and NE. On 2 August the sulfur dioxide gas flux was high at 5,000 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 27-29 July and 1-2 August. The Aviation colour Code remained at Orange (the second highest level on a four-colour scale).

Turrialba | Costa Rica : OVSICORI-UNA reported that during 2-4 August activity at Turrialba was characterized by sporadic, passive gas-and-ash emissions. Events at 0023 and 0700 on 2 August generated diffuse ash plumes that rose 1 km and 300 m, respectively, and drifted W. An event at 1600 on 4 August produced a diffuse ash plume that rose 300 m.