Roundup of Global Volcanic Activity – Ongoing Activity for the week 28 September – 4 October 2022
Aira – Kyushu (Japan) : JMA reported that 11 eruptive events and five explosions at Minamidake Crater (at Aira Caldera’s Sakurajima volcano) were recorded during 26 September-3 October. Volcanic plumes rose as high as 2.8 km above the crater rim and large blocks were ejected as far as 1.7 km from the vent. Incandescence at the crater was visible nightly.
Ebeko – Paramushir Island (Russia) : KVERT reported that moderate activity at Ebeko was ongoing. According to volcanologists in Severo-Kurilsk (Paramushir Island, about 7 km E) explosions generated ash plumes that rose to 3.5 km (11,500 ft) a.s.l. and drifted E during 22-24 and 27-28 September. On 22 and 28 September the ash plumes that drifted E and N produced ashfall in Severo-Kurilsk. A thermal anomaly over the volcano was identified in satellite images on 23 and 28 September.
Great Sitkin – Andreanof Islands (USA) : AVO reported that continuing slow lava effusion at Great Sitkin was confirmed by a 27 September satellite image and likely continued during 28 September-4 October. Elevated surface temperatures were identified during 28-29 September; weather clouds often prevented webcam and satellite views during the rest of the week. Seismicity remained at low levels.
Karthala – Grand Comore Island : According to the Direction Générale de la Sécurité Civile (DGSC) – Comores on 4 October, the Observatoire Volcanologique du Karthala (OVK) reported that activity at Karthala had significantly declined during the previous few days.
Kilauea – Hawaiian Islands (USA) : HVO reported that lava continued to effuse from a vent in the lower W wall of Kilauea’s Halema`uma`u Crater during 27 September-4 October, entering the lava lake. The active part of the lake stayed at a relatively steady level through the week, varying only slightly. Sulfur dioxide emissions were approximately 970 and 1,800 tonnes per day on 28 and 30 September, respectively.
Lewotolok – Lembata Island : PVMBG reported that the eruption at Lewotolok continued during 27 September-4 October. White emissions rose as high as 350 m above the summit and drifted E, SE, W, and NW on most days. White-and-gray plumes rose as high 500 m and drifted NW, W, and E during 29-30 September and 1-2 October.
Merapi – Central Java : BPPTKG reported that the eruption at Merapi continued during 23-29 September and seismicity remained at high levels. As many as seven lava avalanches from the SW lava dome traveled down the Bebeng drainage on the SW flank, reaching a maximum distance of 1.8 km. No morphological changes to the central lava domes were evident in photographs, while the SW dome grew about 1 m taller.
Nevados de Chillan – Central Chile : SERNAGEOMIN reported that two long-period earthquake signals were recorded at Nevados de Chillán at 0813 on 3 October and 1630 on 4 October, and both were followed by a dense ash emission. The ash plume from the first event rose 760 m above the summit and drifted SSW, while the ash plume from the second event rose as high as 1.9 km and also drifted SSW.
Sabancaya – Peru : Instituto Geofísico del Perú (IGP) reported moderate levels of activity at Sabancaya during 5-11 September with a daily average of 46 explosions. Gas-and-ash plumes rose as high as 3 km above the summit and drifted NE, E, and SE. As many as nine thermal anomalies originating from the lava dome in the summit crater were identified in satellite data. Minor inflation continued to be detected near Hualca Hualca (4 km N).
Semeru – Eastern Java : PVMBG reported that the eruption at Semeru continued during 27 September-4 October. Eruptive events at 0459 and 0726 on 2 October produced ash plumes that rose 500-700 m above the summit and drifted S and SW. T
Semisopochnoi – Aleutian Islands (USA) : No ash emissions or explosive activity have been detected since 14 September. Seismicity had decreased, though remained at elevated levels. Steam emissions from the active vent in the N crater of Mount Cerberus persisted. Seismic tremor and a small explosion were detected in seismic and infrasound data during 3-4 October.
Sheveluch – Central Kamchatka (Russia) : KVERT reported that the ongoing eruption at Sheveluch was characterized by explosions, hot avalanches, and lava-dome extrusion during 15-22 September. A daily thermal anomaly was identified in satellite images. Plumes of re-suspended ash drifted 113 km E on 23 September.
Stromboli – Aeolian Islands (Italy) : INGV reported that during 26 September-2 October activity at Stromboli was characterized by ongoing explosions from three vents in Area N (North Crater area) and at least two vents in Area C-S (South-Central Crater area). Low-intensity explosions from the N1 vent (Area N) ejected course material (bombs and lapilli) 80-150 m high at a rate of 3-5 explosions per hour. Spattering was visible at the N2 vent (Area N). Explosions from at least two vents in Area C-S, which were not visible due to the camera views, ejected ash and course material less than 150 m above the vent at a rate of 1-5 events per hour. At 1524 on 29 September an explosion at N2 generated an ash plume that rose 300 m above the summit and ejected abundant amounts of lava fragments, lapilli, and bombs along the Sciara del Fuoco. Four subsequent, low-intensity explosions ejected tephra 100 m high. Spattering activity at the vent intensified afterwards and through the next day. Beginning at 1115 on 3 October a lava flow emerged from Area N and traveled down the Sciara del Fuoco, reaching the ocean.
Suwanosejima – Ryukyu Islands (Japan) : JMA reported that the eruption at Suwanosejima’s Ontake Crater continued during 30 September-3 October. A total of 38 explosions produced eruption plumes that rose as high as 1.6 km above the crater rim and occasionally ejected large bombs from the vent. Crater incandescence was visible nightly and ash sometimes fell in Toshima village (3.5 km SSW).
Taal – Luzon (Philippines) : In a special advisory, PHIVOLCS reported that sulfur dioxide emissions at Taal were as high as 10,718 tonnes per day on 29 September, creating a significant amount of vog over the caldera. Voggy conditions were reported by residents of Laurel, Agoncillo, and Santa Teresita, Batangas. The report noted that sulfur dioxide emissions had been increasing since 15 July and averaged 6,612 tonnes per day in September. In early August degassing at the volcano increased characterized by the upwelling of hot fluids in the lake and steam-rich plumes rising as high as 2.5 km above the lake’s surface.
Ta’u – American Samoa (SW Pacific) : Seismic activity has dramatically decreased and maintained low levels over the past few weeks. Analysis of data from one seismometer that had recorded earthquakes during 2005-2009 suggested that a rate of five detected earthquakes per day was characteristic of long-term background seismicity; the current earthquakes rates were at background levels.
Villarrica – Central Chile : On 3 October SERNAGEOMIN reported that recent passive emissions from Villarrica contained tephra that was deposited on the upper SW flank. Evidence suggested that there were recent fluctuations in the intensity of activity at the lava lake in the main crater.
Whakaari/White Island – North Island (New Zealand) : GeoNet reported that the minor ash and sulfur dioxide emissions from the active vent area in Whakaari/White Island’s crater only occurred on 18 September based on subsequent webcam and satellite images. The most likely cause for the emission was a gas release from small amount of magma moving into the shallow part of the volcano, though there was no evidence of increasing activity at the volcano.