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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 SEC - the eruptive column on 11.23.2021 - photo AIV - Associazione Italiana di Vulcanologia / prof M Viccaro

Etna SEC - the eruptive column on 11.23.2021 - photo AIV - Associazione Italiana di Vulcanologia / prof M Viccaro

Continuation of yesterday's article on the paroxysm of the south-eastern crater of Etna:

(http://www.earth-of-fire.com/2021/10/activity-of-etna-vulcano-cumbre-vieja-and-kilauea.html)

Explosive activity began to abate around 10:00 UTC and essentially ended at 10:30 a.m., as landslides and hot material slides continued in the fracture formed in the southeast flank of the southeastern crater. ; the lava flow emitted by the lower part of the fracture was still advancing on the western flank of the Valle del Bove, having reached an altitude of about 2,300 m.

The eruptive vents in the upper part of the south-eastern crater produced lava fountains which, in the phase of maximum intensity, reached about 800 m in height.

The eruptive column rose, during the culminating phase of the paroxysm, to more than 10 km above sea level. Relapses of pyroclastic material have occurred towards the east-northeast, along an axis that starts from the south-eastern crater passes to the Citelli refuge and crosses the towns of Vena, Presa, Piedimonte Etneo, Taormina and up to to the province of Reggio Calabria. Relapses of lapilli and ash have also been reported by Mascali and Linguaglossa.

Etna Sec - on the left, the flow fed / 13:39 - on the right: supply stopped, flow in cooling / 18:33 - INGV webcam - one click to enlarge
Etna Sec - on the left, the flow fed / 13:39 - on the right: supply stopped, flow in cooling / 18:33 - INGV webcam - one click to enlarge

Etna Sec - on the left, the flow fed / 13:39 - on the right: supply stopped, flow in cooling / 18:33 - INGV webcam - one click to enlarge

INGV field staff report that there is a breach on the southeast side of the CSE, from which the pyroclastic material flows described in previous press releases originate, and from which collapses and small Flows continue to be observed heading towards Valle del Bove reaching an altitude of about 2900 m.
After reaching the maximum amplitude at 10:00 UTC, the volcanic tremor began a rapid descent and at 10:20 UTC, its average values ​​are falling further.
The last location of the tremor, at 09:15 UTC, is near the southeast crater at a depth of about 3.0 km s.l.m.

 

Etna - trémor at 23.10.2021 / 1 p.m. - Doc. INGV


The lava flow emitted by the eastern flank of the CSE, which has spread into the Valle del Bove, seems to be no longer fed and is gradually cooling down. At 17.00 UTC the amplitude of the tremor
volcanic is low. The last location of the tremor, at 4:15 p.m. UTC, is near the Bocca Nuova crater at a depth of about 3.0 km s.l.m. .


The number of infrasound events in the last 10 minutes at 10.12 UTC is very high.
The last infrasonic event is located near the CSE crater.
Analysis of the clinometric data of the paroxysmal event showed variations at different stations, with maximum cumulative values ​​(equal to approximately 3 microradians) recorded at the Cratere del Piano (ECP) station. GNSS network data over the past few hours has not shown any significant changes.

 

Source: INGV OE & INGVvulcani blog

Sheveluch, seen on 24.10.2021 / 07h24 from F.Yu. Levinson-Lessing Kamchatkan Volcanological Station -Klyuchi village, 45 km SSO of the volcano - IVS, KVERT, Weathernews inc.

Sheveluch, seen on 24.10.2021 / 07h24 from F.Yu. Levinson-Lessing Kamchatkan Volcanological Station -Klyuchi village, 45 km SSO of the volcano - IVS, KVERT, Weathernews inc.

Since the beginning of October, the KVERT has been reporting the activity of Sheveluch, and an Orange aviation code. Gas-vapor emissions containing a little ash continue.

On October 24, a plume was reported at 4,000 meters asl. drifting 33 km northeast.

The extrusive eruption continues and ash explosions can occur at any time.

 

Source: KVERT

Bagana - improved SO2 signal in the vicinity of Bagana with 5.66DU of SO2 on 24.10.2021 - Sentinel-5P tropomi

Bagana - improved SO2 signal in the vicinity of Bagana with 5.66DU of SO2 on 24.10.2021 - Sentinel-5P tropomi

Bagana - the bluish arc of sulfur dioxide is visible on the left - image Sentinel-2 bands4,3,2 from 24.10.2021

Bagana - the bluish arc of sulfur dioxide is visible on the left - image Sentinel-2 bands4,3,2 from 24.10.2021

Bagana is an isolated volcano located in the center of Bougainville Island in Papua New Guinea with eruptions dating back to 1842.
The current eruption period began in February 2000, with more recent activity characterized by thermal anomalies as well as gas and vapor plumes and ash (BGVN 44:12 and 45:07). Typical activity consists of episodes of lava flow and strong intermittent passive degassing, particularly of sulfur dioxide.
MIROVA (Middle InfraRed Observation of Volcanic Activity) analysis of MODIS satellite data showed a cluster of intermittent low-power thermal anomalies

Since October, many SO2 emissions have been detected by the Sentinel-5P / Tropomi satellite.

 

Sources: Sentinel-5P / Tropomi, Mounts project, Global Volcanism Program

La Palma / Cumbre Vieja - ash emissions on 23.10.2021 - photo © Daniel Chereau

La Palma / Cumbre Vieja - ash emissions on 23.10.2021 - photo © Daniel Chereau

La Palma / Cumbre vieja - partial collapse of the cone on 23.10.2021 / 11.30 a.m. - Doc. InVolcano

La Palma / Cumbre vieja - partial collapse of the cone on 23.10.2021 / 11.30 a.m. - Doc. InVolcano

In La Palma, four eruptive vents are active in various ways at Cumbre Vieja: emission of ash and pyroclasts, strombolian activity, effusion of lava and white degassing.

On October 23 around 11:30 am, part of the cone collapsed, with strong emission of ash.

The day was marked, according to Daniel Chereau, an on-site observer, by a lot of ash emitted, and a well-fed flow at the base of the cone, with overflows.

Copernicus EMSR reports an extension of the flows over 891.9 ha. And 2,143 buildings destroyed at 23.10 at 07:14 UTC.

La Palma / Cumbre Vieja - the ashes hide the sun - webcam of El Paso on 23.10.2021 via volcanes de Canarias

La Palma / Cumbre Vieja - the ashes hide the sun - webcam of El Paso on 23.10.2021 via volcanes de Canarias

La Palma / Cumbre Vieja - the lava flows at 23.10.2021 / 07:14 UTC - Doc. Copernicus EMST

La Palma / Cumbre Vieja - the lava flows at 23.10.2021 / 07:14 UTC - Doc. Copernicus EMST

Ash emissions remain significant on the morning of October 24.

Seismicity is still recorded, in the same areas, with an increase in intensity.

DSN does not rule out the production of earthquakes of greater magnitude. Yesterday, an earthquake of M4.9 at a depth of 38 km. was felt in the south-east of the island.

La Palma / Cumbre Vieja - Ash plume in the morning of 14.10.2021 - Photo Itahiza

La Palma / Cumbre Vieja - Ash plume in the morning of 14.10.2021 - Photo Itahiza

GEVolcan had access to some samples of "Palmerolitas", igneous rocks composed of two materials of different nature, as is the case of their counterparts the "Restingolitas" on el Hierro.
In principle, these samples would be composed of a white material with a trachytic-rhyolitic composition normally enveloped or encrusted with basaltic sideromelane.
Apparently, according to a known source, this type of rock has also been found in previous eruptions on the island, such as the Teneguía eruption.
Its origin is still the subject of scientific debate.

 

Sources: IGNes, InVolcan, DSN, Copernicus, Volcanes de Canarias, GEVolcan

Samples of "Palmerolitas" - phot GEVolcan

Samples of "Palmerolitas" - phot GEVolcan

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