Friday, 17 February 2023

Volcanos

Roundup of Global Volcanic Activity - Ongoing activity for the week 8 February - 14 February 2023

Ahyi - Mariana Islands (USA) : Unrest at Ahyi Seamount continued during 7-14 February. Pressure sensors on Wake Island, 2,270 km E of Ahyi Seamount, occasionally detected possible activity including possible explosions during 13-14 February. No activity was identified in satellite images, though the image resolutions were too low to detect water discoloration.

Cotopaxi - Ecuador : IG reported that the eruption at Cotopaxi continued during 7-14 February, characterized by daily or almost daily emissions of gas, steam, and ash; inclement weather conditions occasionally prevented views. Gas-and-ash emissions rose as high as 2 km above the crater rim and drifted NW, W, and E during 7-10 February. Minor ashfall was reported in the parish of Tambillo (32 km NNW), Mejia region, on 10 February. Steam-and-gas emissions rose to 1 km and drifted W and SW on 11 February. Gas-and-ash plumes rose around 500 m on 12 February and drifted SW. Minor amounts of ash fell in El Chasqui (17 km W), Mulaló (19 km SW), and San Juan de Pastocalle (20 km WSW). During 13-14 February several steam-and-ash emissions rose as high as 1 km and drifted W and SW. Minor ashfall was reported in Mulaló, San Agustín (11 km W), Ticatilín (15 km WSW), San Ramón (17 km SW), Control Caspi (20 km WSW), and in Pastocalle (22 km W).

Dukono - Halmahera : PVMBG reported that white-and-gray plumes of variable densities rose from Dukono as high as 150 m above the summit and drifted S and E on 8 and 10 February. Inclement weather conditions sometimes prevented visual observations.

Ebeko - Paramushir Island (Russia) : KVERT reported that moderate activity at Ebeko was ongoing during 2-9 February. According to volcanologists in Severo-Kurilsk (Paramushir Island, about 7 km E) explosions during 4-5 and 7-8 February generated ash plumes that rose as high as 4.5 km (14,800 ft) a.s.l. and drifted NE and E. Ashfall was reported in Severo-Kurilsk on 5 and 8 February. A thermal anomaly was identified in satellite images on 8 February.

Great Sitkin - Andreanof Islands (USA) : AVO reported that a 6 February satellite image confirmed continuing lava effusion at Great Sitkin and growth of the flow field to the E; effusion likely continued during 7-14 February. Weather clouds often obscured satellite and webcam views, though steam emissions were observed during 8 and 11-12 February. Seismicity was low most of the week; a network outage began at 2120 on 12 February and prevented transmission of seismic data.

Huaynaputina - Peru : IGP reported that on 4 February a small-to-medium lahar descended the El Volcán drainage, on the S flank of Huaynaputina, and traveled to within 500 m of Quinistaquillas, in the province of Sánchez Cerro, Moquegua region.

Ibu - Halmahera : PVMBG reported that the eruption at Ibu continued during 7-14 February. White-and-gray plumes of variable densities rose as high as 800 m above the summit and drifted NE and NW during 6-7 February.

Kerinci - Central Sumatra : PVMBG reported that the eruption at Kerinci was ongoing during 8-14 February. Ash plumes were visible on most days, though weather conditions prevented views towards the end of the week. At 0724 on 8 February a gray ash plum rose 150 m above the summit and drifted E. Gray-to-brown ash plumes rose 150 m and drifted NE that same day. White-and-gray ash plumes rose 150 m and drifted NE during 9-10 February. At 1740 on 10 February a dense gray ash plume rose around 100 m and drifted E, and on 14 February white-and-brown ash plumes rose 200 m and drifted NE.

Kilauea - Hawaiian Islands (USA) : HVO reported that lava continued to erupt from three locations on Kilauea’s Halema’uma’u Crater floor during 7-14 February. The lava lake in E half of the crater was active and remained at about 10 hectares in size. A small 3-6 m high lava fountain in the S part of the E lake was active during the first few days but had diminished during 10-11 February and remained at lower levels during the rest of the week. The smaller western lake in the basin of the 2021–2022 lava lake as well as the smaller lava pond in the central portion of the crater floor remained active and overflowed frequently each day. Activity in the southern small lava pond had decreased. During 12-14 February a small lava fountain was visible in the smaller central lava pond and was active along with the fountain in the S part of the E lake. Lava continued to overflow the pond and possibly connected to the larger E lava lake.

Lewotolok - Lembata Island : PVMBG reported that the eruption at Lewotolok was ongoing during 7-14 February. Minor crater incandescence at the summit was visible in most of the daily webcam images posted with the daily PVMBG reports. A webcam image captured at 2140 on 11 February showed Strombolian activity. White-and-gray plumes rose as high as 300 m above the crater rim and drifted NE, E, and SE on each day except 9-10 and 14 February due to weather clouds.

Marapi - Central Sumatra : PVMBG reported that the eruption at Marapi continued during 8-14 February. White, gray, and black plumes rose as high as 400 m and drifted SW and S on 10 February. At 1827 a dense black ash plume rose 400 m and drifted NE and E. White-and-gray plumes that were sometimes dense rose as high as 200 m and drifted E and SE on 12 February. Diffuse white-and-gray plumes rose 100 m and drifted N and S on 13 February.

Merapi - Central Java : BPPTKG reported that the eruption at Merapi continued during 3-9 February and seismicity remained at high levels. The SW lava dome produced five lava avalanches that traveled as far as 1.8 km down the SW flank (upstream in the Kali Bebeng drainage) and one pyroclastic flow traveled 1.5 km SW (on 8 February). No significant morphological changes to the central and SW lava domes were evident in webcam images.

Semeru - Eastern Java : PVMBG reported that the eruption at Semeru continued during 6-12 February. Somewhat dense to dense white-and-gray ash plumes rose 300-500 m above the summit and drifted N and NE, though weather conditions often prevented visual observations. At 0623 on 11 February a white-and-brown ash plume rose 600 m above the summit, and at 0754 a dense white-to-gray ash plume rose 600 m and drifted E. At 0527 on 14 February a somewhat-dense, white-to-gray ash plume rose around 800 m. Avalanches of material were detected during the week and sometimes roaring was heard, but they were rarely seen due to weather. Deformation fluctuated and was characterized by overall inflation. The number of earthquakes increased.

Semisopochnoi - Aleutian Islands (USA) : AVO reported that eruptive activity at Semisopochnoi’s Mount Young continued during 7-14 February. Seismicity was low, and a few local earthquakes were recorded during 7-8 February. Steam emissions were visible in webcam images almost daily though views were often cloudy.

Sheveluch - Central Kamchatka (Russia) : KVERT reported that the ongoing eruption at Sheveluch during 2-9 February was generally characterized by explosions, hot avalanches, lava-dome extrusion, and strong fumarolic activity. A daily thermal anomaly was identified in satellite images, and minor ash plumes from lava-dome collapses drifted 110 km NE on 6 February.

Suwanosejima - Ryukyu Islands (Japan) : JMA reported that the eruption at Suwanosejima's Ontake Crater continued during 6-13 February with a total of 10 explosions recorded by the seismic network. The explosions produced eruption plumes that rose as high as 1.5 km above the crater rim and ejected large blocks as far as 400 m from the vent. Crater incandescence was observed nightly. Occasional ashfall was reported in Toshima village (3.5 km SSW).

Tangkuban Parahu - Western Java : PVMBG issued a special report based on recent observations of Tangkuban Parahu. Webcam images captured from 1830 on 9 February to 0300 on 10 February showed incandescence emanating from Ecoma Crater. A team of PVMBG scientists inspected the crater during 1900-2000 on 10 February to identify the source of the incandescence. They observed intense emissions rising from Ecoma Crater, heard roaring and rumbling, and detected a strong sulfur odor, but did not see incandescence. Remote measurements of solfatara temperatures in Ecoma Crater using thermal cameras show varying temperatures, with a maximum of 105 degrees Celsius, and were influenced by airflow conditions at the crater. A multi-gas detector did not record high concentrations of volcanic gases. Seismic data from June 2022 to February 2023 suggested variable rates of fluid movement and increased heating of the subsurface to the surface. Data from monitoring instruments and visual observations indicated that the incandescent was not caused by rising magma and instead by reactions of sulfur deposits around the vents.

Villarrica - Central Chile : The eruption at Villarrica was ongoing during 6-12 February. POVI reported that three explosions were heard during 1940-1942 on 6 February, and then hours later spatter was seen rising 30 m above the crater rim. On 9 February lava fountains were seen rising around 50 m above the crater rim. SERNAGEOMIN noted that in the early part of the week small Strombolian explosions and gas emissions were recorded and observed in webcam images. A period of increased seismicity was recorded on 12 February, after several weeks of stable levels. The seismicity and recent visual observations (especially ash emissions observed on 27 January) indicated that activity was localized at shallow levels, without a clear indication of deep magmatic contribution.

No comments:

Post a Comment