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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
Cerro Negro de Mayasquer (left) and snow-capped Volcán Chiles (right), seen here from the south, are twin volcanoes that straddle the border between Colombia and Ecuador. - photo GVP-04393 / Minard Hall, 1985 (Escuela Politécnica Nacional, Quito) - one click to enlarge

Cerro Negro de Mayasquer (left) and snow-capped Volcán Chiles (right), seen here from the south, are twin volcanoes that straddle the border between Colombia and Ecuador. - photo GVP-04393 / Minard Hall, 1985 (Escuela Politécnica Nacional, Quito) - one click to enlarge

In order to corroborate the existence of changes in the surface activity of the Chiles - Cerro Negro volcanic complex, the IGEPN technicians visited the areas of Aguas Negras, Aguas Hediondas, el Hondón, Potrerillos, El Artezón, Monte Lodo, Lagunas Verdes, La Ecuatoriana, La Virgen y Tablones.

Physical parameters were measured and water samples were taken for geochemical analysis. These will be carried out in the laboratories of the EPN Environmental Research and Control Center (CICAM).

Chiles - Cerro Negro volcanic complex - temperature measurement in the thermal wells of Hondón (Photos: D. Sierra, M. Almeida/IG-EPN).

Chiles - Cerro Negro volcanic complex - temperature measurement in the thermal wells of Hondón (Photos: D. Sierra, M. Almeida/IG-EPN).

Chiles - Cerro Negro volcanic complex - Left: Using a drone to fly over the Hondón area; Right: measurement of gas ratios with MultiGAS equipment (Photos: D. Sierra /IG-EPN).

Chiles - Cerro Negro volcanic complex - Left: Using a drone to fly over the Hondón area; Right: measurement of gas ratios with MultiGAS equipment (Photos: D. Sierra /IG-EPN).

Since April 2022, the CV-CCN has shown a slight increase in seismicity, mainly characterized by the occurrence of volcano-tectonic (VT) type events with two main sources, one located on the SW flank of the Chiles Volcano and a another in the area of ​​los páramos del Ángel. In addition, MultiGAS equipment was used in areas with superficial gas manifestations. Hondón hot spring with 86°C, being possibly the hottest in mainland Ecuador, is one of the most interesting changes that have been presented since there are records (2019).

In addition, what appears to be an inflationary trend has been recorded (which, although it started in 2014), has again shown significant variations since March 2022.

A special report was published on June 14, 2022 summarizing this activity.

Map with earthquakes located in the border area with Colombia, from June 12 at 02:05 (TL) until today June 14 at 08:32 (260 events). The epicenters are concentrated in two areas: south of the Chiles-Cerro Negro volcanic complex and in the Potrerillos area. Earthquakes of greater magnitude are located in this last sector. This area, which corresponds to the Potrerillos area (El Ángel seismic source), has had intermittent seismic activity since 2014. This activity has sometimes been closely linked to seismicity of the CVCCN, occurring in response to increases in seismicity in the volcanic complex or preceding them, the interrelation between these two sources had already been reported in the seismic reports for the years 2018-19

Map with earthquakes located in the border area with Colombia, from June 12 at 02:05 (TL) until today June 14 at 08:32 (260 events). The epicenters are concentrated in two areas: south of the Chiles-Cerro Negro volcanic complex and in the Potrerillos area. Earthquakes of greater magnitude are located in this last sector. This area, which corresponds to the Potrerillos area (El Ángel seismic source), has had intermittent seismic activity since 2014. This activity has sometimes been closely linked to seismicity of the CVCCN, occurring in response to increases in seismicity in the volcanic complex or preceding them, the interrelation between these two sources had already been reported in the seismic reports for the years 2018-19

During the week, more than 15,000 earthquakes were recorded, with the predominance of events associated with rock fracturing, located mainly near the summit and south of the Chiles volcano, with epicenters up to 3.5 km. and depths less than 6 km. from its summit (4700 m altitude). Twenty-two of these events had local magnitudes greater than M2.0, two of which were reported to be felt within the volcanic influence zone, recorded on July 12 at 6:01 p.m. with a magnitude of 3.2 and on July 16 at 10:38 a.m., magnitude 3.3.
In addition, the number of low-energy earthquakes associated with the movement of internal fluids has increased.

 

Source: IGEPN

Piton de La Fournaise - the Dolomieu crater, seen from the Bert trail - photo archives © Bernard Duyck - one click to enlarge

Piton de La Fournaise - the Dolomieu crater, seen from the Bert trail - photo archives © Bernard Duyck - one click to enlarge

Since the beginning of the year, the OVPF has recorded numerous landslides in the Rivière de l'Est sector.

Contrary to what some media report, these landslides are not linked to the activity of the Piton de La Fournaise, but to instabilities along the rampart caused by bad weather.

On the activity side of the volcano, no change since the last monthly bulletin, and no imminence of an eruption.
Indeed, although an inflation of the volcano has been recorded since the end of the last eruption last January, reflecting a replenishment of magma from the surface reservoir, no seismic activity is currently recorded under the summit zone of the volcano.

 

Source : OVPF

Kilauea / Halema'uma'u - overflight of 07.19.2022 - photo J.Chang - USGS - one click to enlarge

Kilauea / Halema'uma'u - overflight of 07.19.2022 - photo J.Chang - USGS - one click to enlarge

In Kilauea, lava eruption from the western Halema'uma'u vent into the active lava lake has continued over the past 24 hours. The lava level of the active surface of the lake remained at the level of the boundary dykes. Seeps were active along the northern rim of the crater floor as of about 4:00 p.m. HST yesterday afternoon and are continuing at this time.

Measurements from an overflight on July 19, 2022 indicated that the crater floor has risen about 133 meters in total and 98 million cubic meters of lava have been shed since this eruption began on September 29, 2021. Summit tiltmeters started a deflationary trend around 9am HST yesterday morning and are transitioning to a flat trend now. A sulfur dioxide (SO2) emission rate of approximately 1,300 tonnes per day (t/d) was measured on July 21, 2022. The summit tremor is stable for the long-term baseline of this eruption .

 

Source: HVO-USGS

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