Volcanos

Roundup of Global Volcanic Activity – Ongoing Activity for the week 20 April – 26 April 2022

Aira – Kyushu (Japan) : JMA reported that very small eruptive events at Minamidake Crater (at Aira Caldera’s Sakurajima volcano) were recorded during 18-25 April. Crater incandescence was periodically visible at night. The sulfur dioxide emissions were slightly high at 1,300 tons per day on 19 April but then dropped to 500 tons per day on 22 April.

Davidof – Aleutian Islands (USA) : AVO lowered both the Aviation Color Code and the Volcano Alert Level for Davidof to Unassigned on 21 April, noting that the earthquake swarm which began in January had declined in the previous few weeks. It is unknown if the swarm was due to tectonic processes or volcanic unrest. The level “Unassigned” means that there is not sufficient instrumentation on the volcano for AVO to characterize a base level of activity; the closest seismometer was on Little Sitkin (15 km E).

Dukono – Halmahera : Based on satellite and wind model data, the Darwin VAAC reported that during 21-23 and 25 April ash plumes from Dukono rose to 2.1 km (7,000 ft) a.s.l. and drifted in multiple directions.

Fuego – South-Central Guatemala :INSIVUMEH reported that 2-10 explosions per hour were recorded at Fuego during 21-25 April, generating ash plumes that rose as high as 1.3 km above the crater rim. The ash plumes mainly drifted as far as 15 km SE, S, and SW causing daily ashfall in areas downwind including Morelia (9 km SW), Panimaché I and II (8 km SW), Santa Sofía (12 km SW), El Porvenir (8 km ENE), Sangre de Cristo (8 km WSW), Finca Palo Verde, Finca la Asunción, El Zapote (10 km S), San Pedro Yepocapa (8 km NW), Ceylon, San Andrés Osuna, and La Rochela. Shock waves rattled structures in communities around the volcano on most days and occasional rumbling was heard. Block avalanches descended the flanks in all directions, but most commonly were visible in the Ceniza (SSW), Seca (W), Trinidad (S), Taniluyá (SW), Honda, and Las Lajas (SE) drainages, often reaching vegetated areas. Explosions ejected incandescent material 100-350 m above the summit during 21-24 April.

Great Sitkin – Andreanof Islands (USA) : AVO reported that slow lava effusion at Great Sitkin continued during 20-26 April, and very low seismicity persisted.

Ibu – Halmahera : PVMBG reported that the eruption at Ibu continued during 22-26 April. Daily dense gray ash plumes generally rose 400-1,500 m above the summit and drifted W and NE, though at 0948 on 25 April ash plumes rose up to 3 km above the summit and drifted W.

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 19-26 April, entering an active lava lake and flowing onto the crater floor. The surface of the lava lake was active all week, and the height of the lake fluctuated; the lake occasionally overflowed the rim, sending lava onto the crater floor. Daily breakouts occurred along the N, NE, E, and S parts of the crater.

Langila – New Britain (Papua New Guinea) : The Darwin VAAC reported that on 24 April an ash plume from Langila rose 2.1 km (7,000 ft) a.s.l. and drifted SW. The plume had dissipated within 5.5 hours.

Lewotolok – Lembata Island : PVMBG reported that the eruption at Lewotolok continued during 19-26 April. Daily white-and-gray ash plumes rose 50-400 m above the summit and drifted W, NW, and E.

Merapi – Central Java : BPPTKG reported that the eruption at Merapi continued during 15-21 April. The heights and morphologies of the SW lava dome and the central lava dome were unchanged from the previous week, and seismicity remained at high levels. As many as 150 lava avalanches traveled a maximum of 2 km mostly down the Bebeng drainage on the SW flank. One pyroclastic flows traveled 2 km SW down the Bebeng.

Pavlof – Alaska Peninsula, Alaska : AVO reported that the eruption at a vent on Pavlof’s upper E flank was ongoing during 20-26 April, though weather conditions sometimes prevented visual observations. Seismic tremor persisted and daily elevated surface temperatures were identified in satellite images.

Popocatepetl – Mexico : CENAPRED reported that the eruption at Popocatépetl continued during 19-26 April. Each day there were 6-27 steam-and-gas emissions that rose from the crater and drifted mainly SW. The plumes sometimes contained ash. Incandescence from the crater was sometimes visible at night. Two minor explosions were recorded at 0152 and 0559 on 21 April.

Rincon de la Vieja – Costa Rica : OVSICORI-UNA reported that a small eruptive event at Rincón de la Vieja was recorded at 0618 on 25 April, though it was not visible due to weather conditions. Another small event was recorded at 0156 on 26 April; the plume was not visible due to conditions.

Sabancaya – Peru : Instituto Geofísico del Perú (IGP) reported moderate levels of activity at Sabancaya during 18-24 April with a daily average of 37 explosions. Gas-and-ash plumes rose as high as 2.3 km above the summit and drifted N, NE, SE, and S. As many as 10 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).

Santa Maria – Southwestern Guatemala : INSIVUMEH reported that the eruption at Santa María’s Santiaguito lava-dome complex continued during 21-25 April. Incandescence from Caliente crater and the lava flows on the W and SW flanks was visible nightly and early mornings. Avalanches of blocks descended the W and SW flanks of Caliente. The lava flows continued to advance, traveling as far as 2.5 km in the San Isidro channel, and produced block avalanches from the ends and sides of the flows that descended the S, SW, and S flanks. Ash from these avalanches fell in areas around the volcano and a sulfur odor was also occasionally noticed.

Semeru – Eastern Java : PVMBG reported that the eruption at Semeru continued during 19-26 April. Almost daily ash plumes were visible rising 200-600 m above the summit that drifted N, S, SW, and W. Cloudy weather sometimes prevented visual observations.

Semisopochnoi – Aleutian Islands (USA) : AVO reported that low-level eruptive activity at Semisopochnoi’s North Cerberus cone continued during 19-26 April. Periods of seismic tremor were occasionally detected and small explosions were recorded in seismic data during 19-20 April. Minor, low-level, plumes with low ash content were visible in webcam images through each day during 19-20 April, with occasional more energetic ash plumes. Weather cloud cover often hindered webcam and satellite views during the rest of the week.

Sheveluch – Central Kamchatka (Russia) : KVERT reported that a thermal anomaly over Sheveluch was identified in satellite images during 15-22 April, and lava-dome extrusion continued. Explosions during 15-16 April produced ash plumes that rose as high as 5 km (16,400 ft) a.s.l. and drifted about 75 km SE.

Suwanosejima – Ryukyu Islands (Japan) : JMA reported that eruptive activity continued to be recorded at Suwanosejima’s Ontake Crater during 18-25 April. Eruption plumes rose as high as 1.5 km above the crater rim; no explosions were recorded.

Wolf – Isla Isabela (Galapagos) : IG reported that thermal anomalies over Wolf were periodically identified in satellite images during 19-26 April, though were absent on several of the days. Lava advancement was identified in images during 19-21 April; no surface activity was visible the rest of the week.

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