Volcanos

Roundup of Global Volcanic Activity – Ongoing Activity for the week 26 January – 1 February 2022

Aira – Kyushu (Japan) : JMA reported that incandescence from Minamidake Crater (at Aira Caldera’s Sakurajima volcano) was visible at night during 24-31 January. Two explosions occurred on 28 January. One of them, recorded at 1319, produced an ash plume that rose 3.4 km above the crater rim and ejected blocks as high as 1.7 km. Ash fell in Arimura (4.5 km SE) and Kurokami (4 km E). JMA noted that until this event explosion plumes had not exceeded 3 km since 5 April 2021.

Davidof – Aleutian Islands (USA) : An earthquake swarm, either related to tectonic processes or volcanic unrest, was recorded in the vicinity of Davidof during 25-26 January. The largest earthquake was a M 4.9 recorded at 1602 on 25 January.Small earthquakes were detected during 27 and 29 January-1 February, though at a lower rate. No anomalous activity was visible in partly-to-mostly cloudy satellite and webcams views. A similar earthquake swarm occurred in December 2021.

Great Sitkin – Andreanof Islands (USA) : AVO reported that slow lava effusion at Great Sitkin continued during 26 January-1 February, though cloudy conditions often prevented satellite and webcam views. Clearer satellite and webcam views during 30-31 January confirmed growth of the flow field, including the W and S lava flows. Elevated surface temperatures were identified in satellite images during 31 January-1 February.

Karymsky – Eastern Kamchatka (Russia) : KVERT reported that a thermal anomaly over Karymsky was visible in satellite images during 23-26 January.

Kilauea – Hawaiian Islands (USA) : HVO reported that lava effusion at the vent of the main cone in the lower W wall of Kilauea’s Halema`uma`u Crater continued intermittently during 26 January-1 February. The lake level fluctuated, reflecting variable lava supply to the lake and periods of inflation and deflation. Lava effused from the vent during 26-28 January, and the W part of the lake was active along with a small pond N of the W vent cone. A few small flows oozed out from the N margin of the lake and an area of spattering in the E part of the crater built a new, small, steep-sided cone. Field crews working near the crater on 27 January heard loud gas-jetting sounds from the new cone. Active lava was no longer visible in the crater by 0800 on 29 January. During 29-30 January the lake was mostly crusted over, though foundering of the crust in the E part of the lake exposed lava and circulating lava was occasionally visible in the small pond N of the main cone. Lava again began flowing from the main cone just before 2130 on 30 January. Lava quickly filled the ponded area just to the N and flowed into the lake. The lake began to rise and overflowed the S margins by midnight, and the N margins by 0500 on 31 January. Lava flows from the S part of the lake fed flows that traveled SE along the walls of the crater until 1100. Multiple ooze outs from the N margin continued through 1 February.

Lewotolok – Lembata Island : PVMBG reported that white-and-gray ash plumes from Lewotolok rose 200 m above the summit and drifted E and SE during 30-31 January.

Merapi – Central Java : BPPTKG reported no significant morphological changes at Merapi’s lava domes, located just below the SW rim and in the summit crater, during 21-27 January. Seismicity remained at high levels. As many as 30 lava avalanches traveled a maximum of 1.8 km SW down the Bebeng drainage, and two pyroclastic flows traveled 2.5 km SW.

Pavlof – Alaska Peninsula, Alaska : AVO reported that the eruption at Pavlof was ongoing during 25 January-1 February, and seismicity was elevated with periods of tremor. A pilot observed the active flow on the E flank on 25 January. Elevated surface temperatures consistent with the lava flow persisted through 30 January; cloud cover prevented views during 31 January-1 February.

Rincon de la Vieja – Costa Rica : OVSICORI-UNA reported that eruptions were recorded at Rincón de la Vieja at 2250 on 26 January, at 0716 and 1050 on 27 January, at 1308 on 30 January, and at 0447 on 1 February. No plumes were visible due to cloud cover or darkness.

Santa Maria – Southwestern Guatemala : In a special bulletin posted on 29 January, INSIVUMEH reiterated that the eruption at Santa María’s Santiaguito lava-dome complex is in a high-extrusion phase. The lava dome in the crater continued to grow and produce avalanches, and two lava flows were active on the W and SW flanks. Seismic data indicated an intensification of descending avalanches starting around 1845 that likely affected the S and SW flanks, though cloudy weather prevented visual confirmation. Notable ashfall was reported in San Marcos Palajunoj (8 km SW), El Palmar (12 km SSW), Quetzaltenango (18 km WNW), and especially in Loma Linda (6 km WSW). Avalanches continued to be detected by the network and seen by OVSAN (Observatorio del volcán Santiaguito) observers through 31 January. The avalanches originated from collapses of the lava flow on the SW flank and descended the W and SW flanks. During 30 January until about 1800 on 31 January a total of 10 pyroclastic flows were detected by the seismic network and observed in webcam images. During 31 January-1 February dense gas emissions rose 600-800 m above the dome, and nighttime incandescence emanated from the dome and the W-flank flow. Avalanches continued to descend the SW and W flanks, several reached the base of the cone.

Semisopochnoi – Aleutian Islands (USA) : AVO reported that low-level eruptive activity at Semisopochnoi’s North Cerberus cone continued during 25 January-1 February. Seismicity was elevated, characterized by periods of tremor and small earthquakes. Steam and low-level ash emissions likely occurred daily, though due to weather clouds they were only confirmed in webcam images during 25-26 and 29-31 January and 1 February. Numerous small explosions were recorded by local seismic and infrasound sensors during 29 January-1 February.

Sheveluch – Central Kamchatka (Russia) : KVERT reported that a thermal anomaly over Sheveluch was identified in satellite images during 21-28 January. Intense steam-and-gas emissions were visible. Gas, steam, and ash plumes drifted 55 km SW on 21 January.

Suwanosejima – Ryukyu Islands (Japan) : JMA reported that incandescence at Suwanosejima’s Ontake Crater was visible nightly during 24-28 January. There were 27 explosions recorded, producing ash plumes that rose at least 3 km above the crater rim and ejected material up to 1 km away from the crater. Rumbling sounds and ashfall were reported in Toshima village (3.5 km SSW). Eruptive activity continued during 28-31 January.

Turrialba – Costa Rica : OVSICORI-UNA reported that three areas of incandescence in Turrialba’s Cráter Oeste were visible during 26-27 January.

Yasur – Vanuatu : The Vanuatu Meteorology and Geohazards Department (VMGD) reported that activity at Yasur continued at a high level of “major unrest,” as defined by the Alert Level 2 status. Ash-and-gas emissions and loud explosions continued to be recorded.

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