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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

A degassing is recorded in the crater of the Fuego volcano at an altitude of 4,300 m above sea level, explosions with weak, moderate and strong characteristics with abundant gas and ash which disperse towards the west and the southwest. These explosions also generate weak and moderate avalanches towards the ravines of the volcano, in particular towards the barrancas Ceniza, Trinidad and Las Lajas. Due to this activity, tephra falls are reported in the communities of Morelia, Panimaché I, Panimaché II.

Ash can be blown away and remain suspended at low levels in the air, creating a hazy environment for several hours which can be detrimental to human health. In the presence of rain, lahars can be generated in all the ravines of the volcano, however, these should be more recurrent and larger in the ravines of El Jute, Las Lajas, Ceniza and Trinidad.

Fuego - image Sentinel bands 4,3,2 + bands 12,11,8A from 10.03.2022 / 4:21 p.m. - via Mounts project 1" - one click to enlarge
Fuego - image Sentinel bands 4,3,2 + bands 12,11,8A from 10.03.2022 / 4:21 p.m. - via Mounts project 1" - one click to enlarge

Fuego - image Sentinel bands 4,3,2 + bands 12,11,8A from 10.03.2022 / 4:21 p.m. - via Mounts project 1" - one click to enlarge

It is not excluded that new lava flows will be generated towards other ravines, as well as the continuation of violent explosions loaded with ash and avalanches of moderate characteristics towards one of the ravines of the Fuego volcano, reason for which one should not stay near or in the canyons of the volcano.

Instructions were given to Conred to inform the communities located near the ravines of Ceniza, Trinidad, Las Lajas and El Jute not to approach or stay in the said ravines, taking into account that the descent of avalanches weak, moderate or even strong can still occur and also cause tephra falls in areas near the volcano. Likewise, in the presence of rain, lahars can be generated, which could be of moderate to strong characteristics in the aforementioned ravines.

 

Source: Insivumeh & Conred

Turrialba - 12.03.2022 in the morning - plume of steam and gas with reflection of light -Ovsicori

Turrialba - 12.03.2022 in the morning - plume of steam and gas with reflection of light -Ovsicori

Turrialba - 12.03.2022 / 07:00 - webcam Ovsicori

Turrialba - 12.03.2022 / 07:00 - webcam Ovsicori

In Costa Rica, the Turrialba has emitted gas and steam, and small amounts of ash, since sunrise March 12, 2022; until about 9:30 a.m. when fog obscured it.

The orange to red color of the morning plume is not related to magma glow but to reflected sunlight.
Seismic activity remains at stable levels, but fluctuates in earthquake frequency.

Poas - 12.03.2022 / 09:28 - Webcam Ovsicori

Poas - 12.03.2022 / 09:28 - Webcam Ovsicori

At Poas, no eruption.

The CO2/SO2 ratio shows a decrease. Convection cells are observed in the lake, some continuous, others sporadic. The SO2 concentration in the view did not exceed 1 ppm.

The temperature of the acid lake was measured with the thermographic camera on March 12, and is 40.1°C.

 

Source: Ovsicori

Laguna caliente du Poas - 12.03.2022 - temperature measurement: 40° C - UNA thermographic camera

Laguna caliente du Poas - 12.03.2022 - temperature measurement: 40° C - UNA thermographic camera

At Wolf volcano, in the Galapagos archipelago, the IGEPN reports on 12.03.2022 / 11 a.m., a volcano-tectonic earthquake during the last 24 hours.

The FIRMS system recorded 159 thermal alerts. The MIROVA system recorded 2 thermal alerts
high (889 MW and 606 MW).

 

The observatory has uploaded an animation of the weekly advance of lava flows in Wolf Volcano. The current eruption began on January 6 this year. The animation was created using information from daily thermal anomalies recorded by NASA's FIRMS satellite system.

 

Sources: IGEPN & Mirova

Researchers have just succeeded in characterizing the deep magmatic system of one of the most active volcanic complexes in the world: the Klyuchevskov volcanic group (KVG) in Kamchatka, Russia.

To study these volcanoes in depth, scientists from the Institute of Earth Sciences in Grenoble, together with their Russian colleagues, used the seismic activity produced by the volcanoes themselves.

The researchers thus monitored certain volcanoes located on the Russian peninsula of Kamchatka. It is one of the largest and most active volcanic complexes in the world. The volcanic activity here results from the subduction of the Pacific plate under the peninsula.

The sources of tremor are distributed in a wide spatial region over the entire range of crustal depths connecting the different volcanoes of the group. Tremor activity is characterized by rapid vertical and lateral migrations explained by rapid pressure transients and dynamic permeability. Our results support the conceptual model of extensive and highly dynamic transcrustal magmatic systems.

Spatial density of tremor sources delineating the active trans-crustal plumbing system below the KVG...

Spatial density of tremor sources delineating the active trans-crustal plumbing system below the KVG...

...  (A) Map of the region studied. The inset shows the location of the Kamchatka Peninsula. Seismic stations are represented by white and black inverted triangles for permanent and temporary networks, respectively. The black dotted rectangle indicates the boundaries of the area used in the grid search. The red dotted line shows a profile for the cross section shown in (C). - (B) Sum along the vertical lines projected onto the horizontal plane. - (C) Sum along horizontal lines with fixed depths and distances along the fault projected onto a vertical plane corresponding to the profile shown in (B). - (D) Similar to (C) but projection on a perpendicular profile illustrated in (B). Tremor hypocenters are represented by open circles. The light magenta crosses in (B), (C) and (D) show the DLP swarms that occurred on November 23, 2015, November 26, 2015 and February 25, 2016. - Doc. Science Advances 02.2022

The results support the conceptual model of extensive and highly dynamic transcrustal magmatic systems.

Published in Science Advances, they show that the active magmatic system is staggering through the entire thickness of the crust. The system would take its source at the base of the crust, at the level of the Moho (about 30 kilometers deep) and would branch upwards to feed several volcanoes through different conduits. The magmatic system could thus extend horizontally over great distances. Thanks to the analysis of the tremors, the researchers can thus define the active zones of the system, and this over the entire height of the crust. and follow their evolution over time. The existence of "plugs" could temporarily prevent the magma from progressing, locally increasing the pressure until rupture. This process would lead to the transient activation of the different zones.

 

 

Source: Science Advances - Seismic tremor reveals active trans-crustal magmatic system beneath Kamchatka volcanoes / Cyryl Journeau & al. -   link

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