Roundup of Global Volcanic Activity – Ongoing Activity for the Week 8 September 2020 – 14 September 2020
Aira | Kyushu (Japan) : JMA reported that very small eruptive events at Minamidake Crater (at Aira Caldera’s Sakurajima volcano) were occasionally recorded during 7-14 September. Nighttime crater incandescence was noted during 9-10 and 12-13 September. The daily sulfur dioxide emission rate was elevated at 1,300 tons/day on 11 September. The Alert Level remained at 3 (on a 5-level scale).
Bezymianny | Central Kamchatka (Russia) : KVERT reported that a new lava dome began growing in the summit crater of Bezymianny around 26 August. A thermal anomaly over the summit was visible during 28-31 August and on 4, 8, and 10 September. Weather clouds sometimes obscured views of the volcano. The Aviation colour Code remained at Yellow (the second lowest level on a four-colour scale).
Dukono | Halmahera (Indonesia) : Based on satellite and wind model data, and information from PVMBG, the Darwin VAAC reported that during 9-14 September ash plumes from Dukono rose 2.1 km (7,000 ft) a.s.l. and drifted in multiple directions. The Alert Level remained at 2 (on a scale of 1-4), and the public was warned to remain outside of the 2-km exclusion zone.
Ebeko | Paramushir Island (Russia) : Volcanologists in Severo-Kurilsk (Paramushir Island), about 7 km E of Ebeko, observed explosions during 4-5 and 10 September that sent ash plumes up to 3.5 km (11,500 ft) a.s.l. and drifted SE and E. The Aviation colour Code remained at Orange (the second highest level on a four-colour scale).
Fuego | Guatemala : INSIVUMEH reported that there were 6-12 explosions per hour at Fuego recorded during 26 August-1 September, generating ash plumes as high as 1.1 km above the crater rim that generally drifted 10-20 km in multiple directions. Shock waves rattled buildings within a 20-km radius. Incandescent material ejected 100-300 m high caused avalanches of blocks in the Ceniza (SSW), Seca (W), Trinidad (S), Taniluyá (SW), Las Lajas, and Honda drainages; avalanches sometimes reached vegetated areas. Ashfall was reported daily in several areas downwind including Morelia (9 km SW), Panimaché I and II (8 km SW), Finca Palo Verde, Santa Sofía (12 km SW), San Pedro Yepocapa (8 km NW), and Sangre de Cristo (8 km WSW). During 10-11 September a lava flow traveled 200 m down the Ceniza and lengthened to 700 m by 12 September; the front of the lava flow generated block avalanches. Strong Vulcanian explosions generated ash plumes that rose over 1.1 km above the crater rim during 11-12 September. Shorter portions of the lava flow were active through 14 September, and by 15 September the flow was 100 m long.
Kadovar | Papua New Guinea : Based on satellite data, the Darwin VAAC reported that on 12 September an ash plume from Kadovar rose to an altitude of 1.8 km (6,000 ft) a.s.l. and drifted W.
Kikai | Japan : JMA reported that during 7-14 September white plumes from Satsuma Iwo-jima, a subaerial part of Kikai’s NW caldera rim, rose as high as 1 km above the Iodake crater rim. Incandescence from the crater was visible at night. The Alert Level remained at 2 (on a 5-level scale).
Manam | Papua New Guinea : The Darwin VAAC reported that on 11 September ash plumes from Manam rose 2.4 km (8,000 ft) a.s.l. and drifted W, based on satellite data and weather models.
Pacaya | Guatemala : On 13 September INSIVUMEH reported that during the previous week activity at Pacaya’s Mackenney Crater was characterized by lava-flow effusion and Strombolian explosions that ejected material as high as 200 m above the vent. Ejected material landed within 50 m of the cone. An active lava flow that had traveled NE was 1,250 m long; another on the N flank was as long as 300 m. Explosive activity rattled houses within a 4-km radius. Lava flows continued to be active during 13-15 September; reaching 600 m long on the NE flank, 300 m long on the N flank, and 400-425 m long (and most active) on the S flank. Strombolian explosions continued to ejected material as high as 200 m.
Reventador | Ecuador : IG reported that a high level of activity continued to be recorded at Reventador. In a special report, IG reviewed the activity had started in mid-June, characterized by strong explosions, the ejection of blocks that rolled down the flanks, and pyroclastic flows that descended the N, NE, and W flanks less than 1 km. Additionally, at the beginning of August, a small lava flow effused at the summit and traveled 400-500 m down the NE flank. Formation of a summit lava dome was also noted on 17 August. The number of thermal alerts was the highest in August compared to the rest of the year. The cone destroyed during a 2002 eruption had been rebuilt and was as tall or slightly taller by 11 September. During 9-15 September gas, steam, and ash emissions observed with the webcam or reported by the Washington VAAC, sometimes multiple times a day, rose as high as 1 km above the summit crater and drifted N, NW, and W. Incandescent blocks rolled down the N flank during 9-10 September and as far as 600 m down the S and SW flanks during 13-15 September. The lava flow on the NE flank had not lengthened.
Semeru | Eastern Java (Indonesia) : According to PVMBG ground-based observers noted ash plumes from Semeru rising 400 m above the summit and drifting S on 14 September. An ash plume rose 500 m and drifted NE the next day. The Alert Level remained at 2 (on a scale of 1-4).
Sheveluch | Central Kamchatka (Russia) : KVERT reported that a thermal anomaly over Sheveluch was identified in satellite images during 4-5 and 8-10 September; weather clouds prevented views during 6-7 and 11 September. The Aviation colour Code remained at Orange (the second highest level on a four-colour scale).
Suwanosejima | Ryukyu Islands (Japan) : JMA reported periodic nighttime incandescence and three explosions at Suwanosejima’s Ontake Crater during 4-11 September. The Alert Level remained at 2 (on a 5-level scale).
Whakaari/White Island | North Island (New Zealand) : On 15 September GeoNet reported continuing but low levels of activity at Whakaari/White Island. Over the previous six weeks the team conducted three flights to measure gas emissions and one for visual observations. The data show that shallow magma was degassing at a high rate through an open, unobstructed system. Temperatures at the gas vents remained high (around 440 degrees Celsius), though that is 100 degrees less than when measured in July. Some of the gas vents had become larger and water had ponded on the crater floor. Continuing subsidence of the active vent areas and the S and W parts of Main Crater wall was indicated by deformation measurements. Volcanic tremor had been generally low, except for a short period in early August. The Volcanic Alert Level was lowered to 1 and the Aviation colour Code remained at Yellow.
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