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Earth of fire

Actualité volcanique, Articles de fond sur étude de volcan, tectonique, récits et photos de voyage

Publié le par Bernard Duyck
Publié dans : #volcanic activity
Etna - Activity at the SE crater and effusive mouth in the Valle del Bove - 12/13/2021 / 9:07 p.m. - courtesy of Pippo Scarpinati - one click to enlarge

Etna - Activity at the SE crater and effusive mouth in the Valle del Bove - 12/13/2021 / 9:07 p.m. - courtesy of Pippo Scarpinati - one click to enlarge

From approximately 16:30 UTC on December 13, 2021, a weak intracrateric Strombolian activity is observed at the SE crater of Etna. From 17:05 UTC the analysis of the images of the CCTV cameras shows the opening of an effusive mouth at the base of the western wall of the Valle del Bove at an altitude estimated between 2200 and 2100 m above sea level, from which a small lava flow is emitted.

The effusive vent produced a poorly fed flow a few hundred meters long. The flow front has been digitized, and its ramifications have reached the Monti Centenari area, settling at an altitude estimated between 1700-1800 m above sea level. In correspondence of the effusive mouth, no visible explosive activity is observed at a distance.
From a seismic point of view, the gradual increase in the mean amplitude of the volcanic tremor continued. It has now reached the high value range. The infrasonic activity, on the other hand, does not show significant variations.
Soil deformation monitoring networks did not record any significant changes.

 

Sources: INGV OE & Pippo Scarpinati.

Whakaari / White Island - situation on 18.11.2021 and on 10.12.2021 - Doc. GeoNet - one click to enlarge

Whakaari / White Island - situation on 18.11.2021 and on 10.12.2021 - Doc. GeoNet - one click to enlarge

Data from an observation flight to Whakaari / White Island last week shows a significant increase in the temperature of the active vent.

The maximum temperature measured in the active ventilation zone was 516 ° C. From September to November 2021, temperatures ranged from 202 ° C to 264 ° C. Temperatures above 500 ° C were last observed in July-August 2021. These observations are consistent with the fact that hot gases continue to be released from the molten rock (magma) beneath the volcano.

A minor amount of ash emission continues to be observed, as on most of our previous flights. These ash deposits remain limited to areas close to active vents. Other intermittent ash emissions may continue to occur.

There was no evidence of additional ash or liquid emission from the vent near the base of the 2019 landslide zone. Gas emissions appeared lower but were not quantified since November 18, 2021. The water level in the lake has dropped during a recent period of good weather.

The current level of activity corresponds to moderate to increased levels of restlessness. As such, the Volcanic Alert Level remains at 2 and the Aviation Color Code remains at yellow.

 

Source: GeoNet

La Palma - risk and containment notice for the Cabildo de Canarias on 12.13.2021 - One click to enlargeLa Palma - risk and containment notice for the Cabildo de Canarias on 12.13.2021 - One click to enlarge

La Palma - risk and containment notice for the Cabildo de Canarias on 12.13.2021 - One click to enlarge

Beyond the eruptive incidents, the biggest problem that the Cumbre Vieja volcano in La Palma produced on Monday was the deterioration of air quality due to the presence of sulfur dioxide in the Aridane Valley. This led to the confinement of the entire population at home between 8.45 a.m. and 1 p.m., when levels improved.

Pevolca management has declared the containment of the municipalities of Los Llanos de Aridane, El Paso and Tazacorte because the air quality in these three areas is "extremely unfavorable" due to the levels of sulfur dioxide derived from the eruption of the La Palma volcano.

Values ​​of 1.522 micrograms / m³ have been measured. The population is advised to close doors, windows, blinds and any air intake from the outside. Confined, if possible, in the most interior rooms. Disconnect ventilation and heating.

La Palma / Cumbre Vieja, flank E mirador de Tajuya - emission of ashes and pyroclasts on 13.12.2021 in the morning - photo Ruben Lopez

La Palma / Cumbre Vieja, flank E mirador de Tajuya - emission of ashes and pyroclasts on 13.12.2021 in the morning - photo Ruben Lopez

La Palma Cumbre Vieja - pyrocumulus seen by the webcams of @ IAC_Astrofisicaen on 13.12.2021 in the evening

La Palma Cumbre Vieja - pyrocumulus seen by the webcams of @ IAC_Astrofisicaen on 13.12.2021 in the evening

Several eruptive pulses occurred yesterday, the most intense around 12:00 and 17:30, with Strombolian activity, and the generation of an eruptive column which reached 6,000 m with emission of pyroclasts.

New collapses occurred in the main building which enlarged the upper crater and that of the secondary cone located on the eastern flank.

Another pulse of great explosiveness was observed at dusk.

The most active lava flows circulate in the central zone with a sufficient flow.

An overflow was reported in the region of Las Norias, in Los Llanos de Aridane, invading land not previously occupied by lava.

The main lava delta (*) continues to be supplied, at its southern end, in the region of Las Hoya.

(*) The correct scientific term to designate these fan-shaped surfaces at the foot of the cliffs which are due to the accumulation of lava which has gained ground from the sea must be "lava delta" (lava delta in English) , confirm the researchers of the University of Las Palmas de Gran Canaria (ULPGC) and of the University of La Laguna (ULL), as it is recognized in the scientific literature. The term "fajana" is a real archaism in the island languages ; in geological terms, a fajana is therefore a deposit of sedimentary slope formed by a mixture of grains of sand and gravel of size, also called colluvion. Therefore, its formation process is sedimentary and not volcanic. (El Pais)

La Palma / Cumbre Vieja - activity of 13.12.2021 - Doc. DSN / IGN

La Palma / Cumbre Vieja - activity of 13.12.2021 - Doc. DSN / IGN

La Palma - variations of the RSAM at 12.13.2021 / 9.45pm - Doc.IGN

La Palma - variations of the RSAM at 12.13.2021 / 9.45pm - Doc.IGN

La Palma / Cumbre Vieja - explosive episodes of 13.12.2021 - Doc. IGN

La Palma / Cumbre Vieja - explosive episodes of 13.12.2021 - Doc. IGN

On 2021-12-13, TROPOMI detected at 14:48 a strong signal of SO2 at a distance of 0.8 km from CumbreVieja with 53.02DU of SO2 at an altitude of about 2 km. Estimated mass within a radius of 300 km: 14.0 kt.

The affected area is estimated to be around 1,193 hectares, with a maximum stream width of 3,350 meters. Seismicity remains low at intermediate depths and the number of earthquakes at depths greater than 20 kilometers remains at very low values.

 

Sources: IGN, IGME, DSN, Copernicus

La Palma - strong SO2 signal at a distance of 0.8 km from CumbreVieja with 53.02DU of SO2 at an altitude of about 2 km. - image Sentinel-5P Tropomi 12/13/2021 / 2:38 p.m. / DLR / BIRA / ESA

La Palma - strong SO2 signal at a distance of 0.8 km from CumbreVieja with 53.02DU of SO2 at an altitude of about 2 km. - image Sentinel-5P Tropomi 12/13/2021 / 2:38 p.m. / DLR / BIRA / ESA

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