Volcanos

Roundup of Global Volcanic Activity - Ongoing Activity for the week of 31 May - 6 June 2017

Aira | Kyushu (Japan) : JMA reported 15 events at Showa Crater (at Aira Caldera’s Sakurajima volcano) during 22-29 May, two of which were explosive. Material was ejected as high as 800 m above the crater rim. Ash plumes rose as high as 3.4 km on 31 May and 3 km on 2 June. Very small events occurred at Minamidake summit crater during 4-5 June. The Alert Level remained at 3 (on a 5-level scale).

Bagana | Bougainville (Papua New Guinea) : Based on analyses of satellite imagery and model data, the Darwin VAAC reported that on 3 and 5 May ash plumes from Bagana rose to altitudes of 1.5-2.1 km (5,000-7,000 ft) a.s.l. and drifted W and SE.

Bogoslof | Fox Islands (USA) : AVO reported that a short-duration (less than 10 minute) explosion at Bogoslof began at 1842 on 31 May based on seismic and infrasound data. A volcanic cloud identified in satellite images rose 7.3 km (24,000 ft) a.s.l., drifted WNW, and dissipated over the Bering Sea. The explosion was preceded by a several hour-long swarm of very small earthquakes. Seismicity decreased in the hours prior to the explosion and remained below the detection threshold. A sulfur dioxide plume from an explosion on 28 May was visible in satellite data drifting over the Hudson Bay region of Canada on 2 June. A short-duration explosive event at 0750 on 5 June produced a small volcanic cloud observed by a pilot. Low-amplitude tremor was detected in seismic data beginning at about 1229 on 5 June but then decreased to background levels. A vessel in the area reported vigorous steaming and a white plume rising several thousand feet above sea level. A brief explosive event was detected at 0600 on 6 June. The event likely produced a low-level (less than 3 km or 10,000 ft a.s.l.) emission; a possible plume at 1.8 km (6,000 ft) a.s.l. was identified in a satellite image following the detection of the activity in seismic and infrasound data, but quickly dissipated. The Aviation colour Code remained at Orange and the Volcano Alert Level remained at Watch.

Cleveland | Chuginadak Island (USA) : AVO reported that no significant volcanic activity at Cleveland was detected in seismic, infrasound, or cloudy satellite images during 31 May-5 June. The webcam recorded steam emissions during periods of clear weather. Small low-frequency events were recorded by the seismic station located on the flank of the volcano beginning at 0939 on 6 June. The events were consistent with lava-dome growth, but growth could not be visually confirmed. The Aviation colour Code remained at Orange and the Volcano Alert Level remained at Watch.

Colima | Mexico : On 2 June the Centro Universitario de Estudios e Investigaciones de Vulcanologia - Universidad de Colima reported that during the previous week seismic data revealed 21 high-frequency events, 14 long-period events, 1.7 hours of tremor, 12 landslides, and zero explosions. During 25-26 May sulfur dioxide emissions were low at 35-51 tons per day, close to the detectable limits.

Dukono | Halmahera (Indonesia) : Based on analyses of satellite imagery, wind model data, and notices from PVMBG, the Darwin VAAC reported that during 31 May-6 June ash plumes from Dukono rose to altitudes of 1.8-2.4 km (6,000-8,000 ft) a.s.l. and drifted NW, W, SW, and E.

Ebeko | Paramushir Island (Russia) : Based on observations by residents of Severo-Kurilsk (Paramushir Island) about 7 km E of Ebeko, KVERT reported that explosive activity continued at the volcano during 25 May-2 June. The Aviation colour Code remained at Orange (the second highest level on a four-colour scale).

Fuego | Guatemala : INSIVUMEH reported increased activity at Fuego on 1 June, characterized by an increase in the number of explosions (6-7 per hour) and ash plumes rising as high as 950 m above the crater and drifting W. Explosions generated shock waves that rattled structures in multiple areas including Panimaché I and II (8 km SW), Morelia (9 km SW), Santa Sofía (12 km SW), El Porvenir, and Sangre de Cristo (8 km WSW). Incandescent material was ejected as high as 500 m above the crater rim, and caused avalanches of material on the flanks. On 2 June explosions produced ash plumes that rose 550-950 m and drifted 10-12 km W and SW. Shock waves were detected within a radius of 25 km. Incandescent material was ejected 300-500 m high, causing avalanches in the Ceniza (SSW), Taniluyá (SW), and Santa Teresa (W) drainages. During 3-4 June there were 2-4 explosions recorded per hour. Ash plumes rose 650-1,050 m high and drifted 8-10 km W and SW. Weak shock waves rattled nearby buildings. Avalanches from ejected incandescent material continued to descend the three drainages. On 4 June a hot lahar descended the Pantaleón (W) drainage, carrying blocks more than 2 m in diameter, branches, and tree trunks. The lahar was 30 m wide and had a strong sulfur odor. During 4-5 June incandescent material rose 150 m and a lava flow traveled 300 m down the Santa Teresa drainage. On 6 June INSIVUMEH noted that eruptive episode number five had ended, with remnant lava flows in the Santa Teresa (2 km long) and Ceniza (3 km long) drainage. Explosions generated ash plumes that rose 950 m and drifted 15 km W and NW.

Ibu | Halmahera (Indonesia) : PVMBG reported that eruptions at Ibu on 1 and 5 June generated ash plumes that rose 150-250 m above the crater and drifted N and SE, respectively.

Kilauea | Hawaiian Islands (USA) : During 31 May-6 June HVO reported that the lava lake continued to rise, fall, and spatter in Kilauea’s Overlook crater. Webcams recorded incandescence from long-active sources within Pu'u 'O'o Crater, from a vent high on the NE flank of the cone, and from a small lava pond (which had many small spattering sites along the margin) in a pit on the W side of the crater. The 61G lava flow, originating from a vent on Pu'u 'O'o Crater's E flank, continued to enter the ocean at Kamokuna. Field observations on 31 May revealed that the lava delta had grown to an area of approximately 0.01 square kilometers. A solidified lava ramp extended from the tube exit high on the sea cliff down to the delta, whose leading edge was about 100 m from the tube exit on the sea cliff.

Klyuchevskoy | Central Kamchatka (Russia) : KVERT reported that a weak thermal anomaly over Klyuchevskoy was identified in satellite images during 27 and 30-31 May and 2 June. Explosions during 1-2 June generated ash plumes that rose to 6 km (19,700 ft) a.s.l. and drifted about 400 km SSE. Ash plumes drifted over Petropavlovsk-Kamchatsky and Elizovo. 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 wind model data, the Darwin VAAC reported that on 1 June ash plumes from Langila rose 1.8 km (6,000 ft) a.s.l. and drifted N and NW.

Manam | Papua New Guinea : RVO reported that although weather clouds often obscured views of Manam during 1-7 June white emissions were periodically seen rising from Southern Crater and Main Crater. Seismicity was very low. The Alert Level remained at Stage 1.

Planchon-Peteroa | Central Chile-Argentina border : Based on Observatorio Volcanológico de los Andes del Sur (OVDAS) - SERNAGEOMIN observations, ONEMI reported on 17 May that the number and magnitude of earthqaukes at Planchón-Peteroa had gradually declined during the past months, reaching baseline levels. Minor to no surface activity was noted. OVDAS-SERNAGEOMIN lowered the Alert Level to Green (the lowest level on a three-colour scale), and ONEMI canceled the Yellow Alert for the communities of Molina (66 WNW), Curicó (68 km NW), Romeral (75 km NW), and Teno (68 km NW) that had been in place since 1 July 2016.

Poas | Costa Rica : OVSICORI-UNA reported that tremor amplitude at Poás fluctuated from low to medium levels during 30-31 May, often associated with the vigor of emissions of water vapor, magmatic gases, and material from vents. An event at 1200 on 2 June generated a plume consisting of water vapor, gases, and minor amounts of ash that rose 600 m above the crater. Another event recorded at 1353 could not be confirmed visually due to weather conditions. An event at 0858 on 6 June generated a plume that rose 1 km.

Popocatepetl | Mexico : Each day during 31 May-2 June CENAPRED reported 51-78 and steam and gas emissions from Popocatépetl; the daily count increased to 144-276 during 2-5 June. Explosions were detected during 31 May-1 June (1-2 per day) and during 2-5 June (13-22 per day) though cloudy conditions prevented visual confirmation of ash, gas, and steam plumes. Observers noted material being ejected 200 m from the crater on 3 June. Crater incandescence was visible on some nights. The Alert Level remained at Yellow, Phase Two.

Sabancaya | Peru : Observatorio Vulcanológico del Sur del IGP (OVS-IGP) and Observatorio Vulcanológico del INGEMMET (OVI) reported that for the second week in a row explosive activity at Sabancaya slightly increased from the previous week; there was an average of 47 explosions recorded per day during 29 May-4 June. Seismicity was dominated by long-period events, and the number and magnitude of hybrid events were low. Gas-and-ash plumes rose as high as 3 km above the crater rim and drifted more than 40 km E and SE. The MIROVA system detected five thermal anomalies, spread over the SE, N, and NW flanks. Sulfur dioxide flux was as high as 1,703 tons per day on 3 June.

Sinabung | Indonesia : Based on PVMBG observations, webcam and satellite images, and wind data, the Darwin VAAC reported that during 31 May-5 June ash plumes from Sinabung rose 3.4-5.5 km (11,000-18,000 ft) a.s.l. and drifted in multiple directions.

Turrialba | Costa Rica : OVSICORI-UNA reported that volcano-tectonic amplitude at Turrialba fluctuated from low to moderate levels during 30-31 May. Plumes of water vapor, magmatic gases, and material rose no higher than 300 m above the crater rim, sporadically contained ash, and drifted NW. On 3 June at 1930 an event produced an ash plume that rose 300 m and drifted SW. The report noted that during the previous week ash emissions had been sporadic and not generated by explosions.