Volcanos

Roundup of Global Volcanic Activity – Ongoing Activity for the week 14 September – 20 September 2022

Aira – Kyushu (Japan) : JMA reported that 10 explosions at Minamidake Crater (at Aira Caldera’s Sakurajima volcano) were recorded during 12-19 September. Volcanic plumes produced by the explosions rose as high as 1.6 km above the crater rim and ballistics were ejected as far as 1.3 km from the vent. Sulfur dioxide emissions were high at 2,400 tons per day on 24 September. Nighttime incandescence at the crater was visible during 2-16 September.

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 up to 3.6 km (11,800 ft) a.s.l. and drifted in multiple directions. A thermal anomaly over the volcano was identified in satellite images during 8 and 12-13 September. Ash fell in Severo-Kurilsk during 9-10 September.

Fagradalsfjall – Iceland : IMO stated that the Fagradalsfjall and Krýsuvík-Trölladyngja volcanic systems have been designated as two separate systems based on previous scientific research combined with data collected and analyzed from the two recent eruptions (2021 and 2022). On 15 September lava from the fissure that opened in Meradalir stopped erupting on 21 August. Seismicity remained at low levels and no deformation was detected.

Great Sitkin – Andreanof Islands (USA) : AVO reported that slow lava effusion at Great Sitkin likely continued during 13-20 September, an analysis confirmed by clear satellite images during 13-15 September. Lava flowed outward from the vent area but flows at the margins did not advance. Minor steam emissions were also visible during 13-14 September and elevated surface temperatures were identified during 13-15 and 17-18 September. Weather cloud cover occasionally prevented webcam and satellite views. A data outage affected the local seismic network during 16-20 September, though no significant activity was detected on regional geophysical networks.

Ibu – Halmahera : PVMBG reported that the eruption at Ibu continued during 14-20 September. Gray-and-white ash plumes of variable densities rose as high as 800 m above the summit and drifted in multiple directions.

Kadovar – Northeast of New Guinea : Based on satellite and wind model data, the Darwin VAAC reported that on 18 September multiple, discrete, ash plumes from Kadovar rose to an altitude of 1.5 km (5,000 ft) a.s.l. and drifted NW and WNW.

Karymsky – Eastern Kamchatka (Russia) : KVERT reported that a weak thermal anomaly over Karymsky was identified in satellite images during 9 and 10-11 September.

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 13-20 September, entering the lava lake and flowing onto the crater floor. Part of the lake’s surface was continuously active.

Krysuvik-Trolladyngja – Reykjanes Peninsula : IMO stated that the Fagradalsfjall and Krýsuvík-Trölladyngja volcanic systems have been designated as two separate systems based on previous scientific research combined with data collected and analyzed from the two recent eruptions (2021 and 2022). On 15 September the Aviation Color Code for Krýsuvík-Trölladyngja was changed to Green, reflecting that the activity was at known background levels.

Lewotolok – Lembata Island : PVMBG reported that the eruption at Lewotolok continued during 13-20 September. Daily white emissions rose as high as 300 m above the summit and drifted in multiple directions. During 16-19 September white-and-gray or white, gray, and black plumes rose as high 1 km and drifted W and NW. Incandescence above the crater rim was visible in some webcam photographs posted during 14-15 September.

Merapi – Central Java : BPPTKG reported that the eruption at Merapi continued during 9-15 September and seismicity remained at high levels. As many as 13 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 SW and central lava domes were evident in photographs.

Nevados de Chillan – Central Chile : SERNAGEOMIN reported that a long-period earthquake signals were recorded at Nevados de Chillán at 0750 and 1913 on 19 September. Associated emissions at 0750 rose 1.1 km above the summit and drifted NE, and at 1913 rose 1.7 km above the summit and drifted SE. The Alert Level remained at Yellow, the second lowest level on a four-color scale, and residents were reminded not to approach the crater within 3 km.

Pavlof – Alaska Peninsula, Alaska : AVO reported that a minor eruption at a vent on Pavlof’s upper E flank was ongoing during 13-20 September. Seismic tremor persisted. New lahar and minor ash deposits extending less than 900 m from the vent were visible during 11-13 September. Strong incandescence at the vent and from an area within 200 m downslope was visible in webcam images starting on 14 September, signifying the emplacement of a short lava flow. Elevated surface temperatures over the vent and flow were identified in satellite images through 20 September; lava effusion continued but no active lava flows extended down the flank from the vent. Explosions were recorded during 18-19 September and steam emissions were visible in webcam images during 19-20 September.

Purace – Colombia : Observatorio Vulcanológico y Sismológico de Popayán, Servicio Geologico Colombiano (SGC), reported that during 13-19 September the number of earthquakes at Puracé was slightly higher compared to previous weeks. A seismic swarm was recorded on 15 September. Events were located about 1.5 km SW of Puracé crater, at depths of 3-4 km, and were as large as M 1.3. A total of 904 earthquakes were recorded during the week; 296 of those were volcano-tectonic events, 538 were long-period events, 54 were low-energy pulses of tremor, 11 were tornillo-type events, and five were hybrid events. Data from the GNSS (Global Navigation Satellite System) geodetic network indicated continuing inflation. White gas plumes were visible in the Anambío, Mina, Lavas Rojas, Cerro Sombrero, and Curiquinga webcams drifting NW. Sulfur dioxide emissions were as high as 2,021 tonnes per day.

Rincon de la Vieja – Costa Rica : OVSICORI-UNA reported continuing eruptive activity at Rincón de la Vieja characterized by occasional small phreatic explosions. A small explosion at 0147 on 14 September produced a steam-and-gas plume that rose 600 m above the crater rim. Low-frequency tremor began at 0900 on 17 September and was possibly associated with small eruptive events, though they were not visually confirmed. A possible emission was recorded at 0219.

Semeru – Eastern Java : PVMBG reported that the eruption at Semeru continued during 13-20 September. Eruptive events at 0524 on 17 September and 0505 on 19 September produced ash plumes that rose 500 m above the summit and drifted W and SW. The Alert Level remained at 3 (on a scale of 1-4). The public was warned to stay at least 5 km away from the summit, and 500 m from Kobokan drainages within 17 km of the summit, along with other drainages originating on Semeru, including the Bang, Kembar, and Sat, due to lahar, avalanche, and pyroclastic flow hazards.

Semisopochnoi – Aleutian Islands (USA) : AVO reported that the eruption at Semisopochnoi was ongoing during 13-20 September. Seismicity remained elevated and characterized by intermittent tremor. Low-level ash emissions from the N crater of Mount Cerberus were occasionally visible in mostly cloudy webcam views during 13-15 September. Possible fresh local ashfall was seen in webcam images during 16-17 September. Steam emissions were visible in webcam views during 19-20 September.

Sheveluch – Central Kamchatka (Russia) : KVERT reported that the ongoing eruption at Sheveluch was characterized by explosions, hot avalanches, and lava-dome extrusion during 8-15 September. A daily thermal anomaly was identified in satellite images. Plumes of re-suspended ash drifted 90 km E on 8 September.

Suwanosejima – Ryukyu Islands (Japan) : JMA reported that the eruption at Suwanosejima’s Ontake Crater continued during 12-19 September. A total of 11 explosions produced eruption plumes that rose as high as 1.4 km above the crater rim and ejected large blocks 600 m from the vent. Volcanic tremor was occasionally recorded.

Whakaari/White Island – North Island (New Zealand) : GeoNet reported that minor ash emissions from the active vent area in Whakaari/White Island’s crater were visible in webcam images on 18 September. The Aviation Color Code was raised to Orange; the Volcanic Alert Level remained at 2. Minor light brown ash emissions were visible through the day, and rose no higher than 600 m above the volcano. Ash emissions were not visible beyond the island, but a steam plume was seen from the Bay of Plenty coast. A strong sulfur dioxide signal associated with the emissions was identified in satellite images that same day. One of the seismic stations began working again on 19 September and showed typical low-level seismicity, consistent with no visible ash emissions. GeoNet was unable to accurately characterize the ash emissions due to the lack of data from inoperable instruments and the semi-operational webcam on the island. They noted that the most likely cause was a small amount of magma moving into the shallow part of the volcano.

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