Volcanos

Roundup of Global Volcanic Activity – Ongoing Activity for the week 16 March – 22 March 2022

Aira – Kyushu (Japan) : JMA reported that very small eruptive events were recorded at Minamidake Crater (at Aira Caldera’s Sakurajima volcano) during 14-21 March. Crater incandescence was visible at night. The sulfur dioxide emission rate was slightly high at 1,300 tons per day on 17 March.

Great Sitkin – Andreanof Islands (USA) : AVO reported that slow lava effusion at Great Sitkin continued during 15-22 March and very low seismicity persisted. Cloud cover prevented views of the volcano most of the week; slightly elevated surface temperatures were identified in satellite images during 20-21 March.

Karymsky – Eastern Kamchatka (Russia) : KVERT reported that a thermal anomaly over Karymsky was visible in satellite images during 13-16 March. The volcano was either quiet or obscured by clouds on the other days during 11-18 March.

Kilauea – Hawaiian Islands (USA) : HVO reported that lava effusion from vents in the lower W wall of Kilauea’s Halema`uma`u Crater continued at variable rates during 15-22 March; effusion briefly paused during 0145-0445 on 18 March. Lava flowed in the active W part of the lava lake causing circulation in the lake that was visible on most days. At around 0700 on 16 March a lava flow originating from the embayment just N of the western vent area traveled NW onto the crater floor; this flow periodically advanced through the week. Ooze outs of lava along the lake’s margins were visible on a few of the days; a notable one began along the N margin at 0345 on 21 March and persisted through the next day.

Lewotolok – Lembata Island : The eruption at Lewotolok continued during 15-22 March according to PVMBG. Almost daily white-and-gray ash plumes rose as high as 600 m above the summit and drifted in multiple directions. Crater incandescence, lava effusion, and rumbling sounds were reported on most days.

Merapi – Central Java : BPPTKG reported no significant morphological changes at Merapi’s summit lava dome during 11-17 March, but the height of the dome below the SW rim had decreased by 2 m. Seismicity remained at high levels; the intensity of the signals had increased compared to the previous week. As many as 119 lava avalanches originating from the SW dome traveled a maximum of 2 km down the Bebeng drainage on the SW flank. Four avalanches traveled no more than 1 km SE down the Gendol drainage.

Nevados de Chillan – Central Chile : SERNAGEOMIN reported that lava in Nevados de Chillán’s Nicanor Crater was observed in satellite images on 1 March and coincided with elevated thermal temperatures also identified in satellite images. A higher resolution satellite image acquired on 15 March showed the extrusive lava feature in more detail; it was about 33 x 57 m elongated E-W, and had irregular edges. The emplacement of the lava was contemporaneous with nighttime crater incandescence and moderate explosive activity. Steam plumes with occasional tephra content rose to heights less than 1.5 km above the crater rim. Seismic activity had steadily declined since January. During the first half of March sulfur dioxide emissions averaged 454 tons per day, peaking at an anomalously high value of 2,348 tons per day on 13 March.

Nyamulagira – DR Congo : Active lava on Nyamulagira’s crater floor was visible in satellite images during 8-13 March.

Nyiragongo – DR Congo : Lava effusion from vents on Nyiragongo’s crater floor continued during 13-18 March based on satellite images. Significant gas emissions were visible drifting SW on 13 March.

Pavlof – Alaska Peninsula, Alaska : AVO reported that the eruption at a vent on Pavlof’s upper E flank was ongoing during 15-22 March, and seismic tremor persisted. Cloud cover sometimes prevented webcam and satellite views of the summit area, though almost-daily elevated surface temperatures identified in satellite images were consistent with minor lava effusion. Three small explosions were detected in local and regional infrasound data during 19-20 March.

Reventador – Ecuador : IG reported that a high level of activity continued at Reventador during 15-22 March, though cloudy weather conditions sometimes prevented visual observations. Steam-and-ash plumes, often observed multiple times a day with the webcam or reported by the Washington VAAC, rose as high as 1 km above the summit crater and drifted mainly NW, W, and SW. Crater incandescence was visible most nights; incandescent material was visible descending the S flank during 15-16 March.

Rincon de la Vieja – Costa Rica : OVSICORI-UNA reported that eruptive events at Rincón de la Vieja were recorded at 0405 on 19 March, 1402 on 20 March, and 0350 on 22 March. The events lasted 1-8 minutes each and no plumes were visible due to weather conditions.

Sangay – Ecuador : IG reported a high level of activity at Sangay during 15-22 March. Weather clouds and rain often prevented visual and webcam observations of the volcano, though daily ash-and-gas plumes were identified in satellite images by the Washington VAAC or in webcam views; plumes rose as high as 1 km above the volcano and drifted N, NW, W, and SW. Multiple daily thermal anomalies over the volcano were visible in satellite data. Emissions of incandescent material were occasionally visible in webcam images. The seismic network detected signals indicating descending lahars on 17, 19, and 21 March.

Semeru – Eastern Java : PVMBG reported that the eruption at Semeru continued during 15-22 March, though weather conditions sometimes hindered views. Daily eruptive events produced white-and-gray plumes that rose 200-800 m above the summit and drifted mainly N, W, and SW. At 0353 on 22 March a pyroclastic flow originating from the end of a lava flow descended the Kobokan drainage on the SE flank and produced an ash cloud that rose 1.5 km above summit and drifted SE.

Semisopochnoi – Aleutian Islands (USA) : AVO reported that low-level eruptive activity at Semisopochnoi’s North Cerberus cone continued during 15-22 March. Periods of seismic tremor and occasional small explosions were detected daily in seismic and regional infrasound data. Daily minor ash emissions and occasional steam emissions were visible in webcam images.

Sheveluch – Central Kamchatka (Russia) : KVERT reported that a thermal anomaly over Sheveluch was identified in satellite images during 11-18 March. An ash cloud was identified in satellite images drifting 50 km WNW at an altitude of 4.5 km (14,800 ft) a.s.l. on 15 March.

Soufriere St. Vincent – St. Vincent : UWI Seismic Research Centre and National Emergency Management Organisation (NEMO) lowered the Alert Level for Soufrière St. Vincent to Green (the lowest level on a four-color scale) on 16 March, noting that seismic and fumarolic activity were at or below background levels recorded prior to the 2020-2021 eruption. The La Soufriere trail remained closed due to the uneven and dangerous terrain. The public was reminded about lahar hazards during heavy rains.

Suwanosejima – Ryukyu Islands (Japan) : JMA reported that eruptive activity continued to be recorded at Suwanosejima’s Ontake Crater during 14-21 March. As many as 27 explosions were recorded, and crater incandescence was visible nightly. Eruption plumes rose as high as 1.9 km above the crater rim and ejected blocks 300-500 m away from the crater. Ashfall was reported as far as 5 km away, including in Toshima village (3.5 km SSW) during 18-21 March.

Whakaari/White Island – North Island (New Zealand) : On 23 March GeoNet reported that volcanologists observed Whakaari/White Island and took gas measurements during overflights the week before. The active vent area had subsided, and small collapses in one of the 2019 craters had occurred in between the flights. During the second flight, scientists observed geysering from a small, gray-colored pool on the S side of the main crater. In just over an hour the pool was gone and a collapse pit was in its place. Diffuse ash emissions had ceased. Gas and temperature measurements were lower (290 degrees Celsius) compared to the previous month.

Wolf – Isla Isabela (Galapagos) : IG reported that the eruption at Wolf continued during 15-22 March. Daily thermal alert counts, as many as around 176, indicated active and advancing lava flows on the SSE flank.

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