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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
Nevado del Ruiz - ash emissions from the last days - Doc. SGC

Nevado del Ruiz - ash emissions from the last days - Doc. SGC

The Servicio Géologico Colombiano informs the authorities and the community that in recent days, the snow-capped volcano Nevado del Ruiz (VNR) has presented small emissions of ash associated with seismic signals of low energy level.

A 10 MW thermal anomaly c was observed by Mirova on 10.03.2020 / 03h35.

On March 10, three gas and ash emissions were recorded today at 07:42 h 10:29 and 10:55 (local time), with column heights measured at the top of the volcano of 696, 346 and 552 m respectively, with a dispersion influenced by the wind direction and speed, which varied from the southwest to the southeast of the volcano.

Very fine ash fall is possible near the volcano and in populations located in the direction of the wind regime.

The different monitoring parameters show that the volcanic system is still unstable, which can give rise to new ash emissions.

The level of activity continues in yellow or (III): Changes in the behavior of volcanic activity.

 

Source: SGC

Nevado del Ruiz - thermal anomalies on 10.03.2020 / 6:50 p.m. - note on the bottom graph, the largest number of thermal anomalies spotted since December 2019 - Doc. Mirova_MODIS_logVRP

Nevado del Ruiz - thermal anomalies on 10.03.2020 / 6:50 p.m. - note on the bottom graph, the largest number of thermal anomalies spotted since December 2019 - Doc. Mirova_MODIS_logVRP

The Phivolcs raised the Kanlaon alert level from normal to abnormal / 1, following an increase in seismicity and inflation in the summit area.

Since March 9, 2020, 80 volcanic earthquakes, including 77 low frequency earthquakes (associated with magmatic fluids); since the end of January 2020, the parameters indicate a marked inflation of the upper slopes of the volcano.

This situation of instability can lead to a phreatic eruption or a magmatic intrusion.

Level 1 is associated with the ban on entering a radius of 4 km, and the aviation council to avoid flights near the summit.

 

Source: Phivolcs

Kanlaon - the historically active Lugud crater - photo 03.2010 / Billy Lopue, used under Creative Common BY-NC-ND 2.0 / GVP

Kanlaon - the historically active Lugud crater - photo 03.2010 / Billy Lopue, used under Creative Common BY-NC-ND 2.0 / GVP

During the period from March 2 to 8 (posted online on March 10), the INGV provides information on the activity of the upper craters of Etna, mainly characterized

- by Strombolian explosions and an effusion at the level of Voragine (VOR),

- and degassing with intermittent intermittent ash emission of strombolian ash from the new south-east crater (NSEC) and the north-east of the crater (NEC).

At the seismicity level, there is a low seismic fracturing activity and a stationary state of the volcanic tremor parameters. The infrasonic activity remains moderate. No significant deformation. The flow of SO2 is at an average level. The flow of CO2 from soils is at medium-low levels.

 

Source: INGV OE

 Etna - activity of 03.03.2020 in the evening - photo Boris Behncke

Etna - activity of 03.03.2020 in the evening - photo Boris Behncke

Etna - Map of the summit crater area (DEM 2014, Laboratory of aerogeophysics - Section Rome 2, mod.). Scalloped black lines = edge of upper craters: BN = Bocca Nuova, inside of which BN-1 and BN-2 are observed; VOR = sinkhole; NEC = Northeast Crater; SEC = Southeast Crater; NSEC = New Southeast Crater. Yellow dots = degassing vents. Red dots = mouths with eruptive activity. red line = active molded parts. Yellow lines = pouring in cooling. Gray circle = ash cone. - Doc. INGV OE

Etna - Map of the summit crater area (DEM 2014, Laboratory of aerogeophysics - Section Rome 2, mod.). Scalloped black lines = edge of upper craters: BN = Bocca Nuova, inside of which BN-1 and BN-2 are observed; VOR = sinkhole; NEC = Northeast Crater; SEC = Southeast Crater; NSEC = New Southeast Crater. Yellow dots = degassing vents. Red dots = mouths with eruptive activity. red line = active molded parts. Yellow lines = pouring in cooling. Gray circle = ash cone. - Doc. INGV OE

Whakaari / White Island remains in a high state of agitation.

The volcanic alert level remains at level 2; The aviation color code remains yellow.

Aerial observations confirm the overall drop in CO2 and SO2 production since the December 9, 2019 eruption, although the latest data shows slightly high amounts of gas compared to recent measurements.

A thermal infrared helicopter survey recorded a temperature of 746 ° C. This was measured on one of the lava lobes and is the warmest temperature measured to date. Despite these high temperatures of fumaroles, a small pond of water is present in the primary crater formed on December 9, 2019. Small-scale jets of this pond water continue to occur, as the activity observed in September-December 2019.

 

High temperatures and large amounts of gas are consistent with the continued presence of shallow magma below the main vent zone and fall within the expected range of fluctuation for post-eruptive processes. The active vent zone remains a rapidly changing environment and an eruption could occur with limited warning signs.

 Plausible triggers for an eruption include the collapse of unstable materials around the vents, the sudden release of magma gas, and the rapid entry of water onto the shallow magma body.

The volcanic alert level remains at level 2. The aviation color code remains yellow.

 

Source: GeoNet

Whakaari White Island - photo NZ Geo 02.2020

Whakaari White Island - photo NZ Geo 02.2020

White island - gas plume of 10.03.2020 / 9.30 a.m. NZDT - White island crater floor webcam / GeoNet

White island - gas plume of 10.03.2020 / 9.30 a.m. NZDT - White island crater floor webcam / GeoNet

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