July 21 , 2017. EN. Nevados de Chillan , Copahue , Piton de la Fournaise , Karymsky , Sabancaya .

Home / blog georges Vitton / July 21 , 2017. EN. Nevados de Chillan , Copahue , Piton de la Fournaise , Karymsky , Sabancaya .

July 21 , 2017. EN. Nevados de Chillan , Copahue , Piton de la Fournaise , Karymsky , Sabancaya .

July 21 , 2017.

 

Nevados de Chillan , Chile :

During this period, 511 seismic events were recorded, of which 50 were classified as volcano-tectonic (VT) events in relation to rock fracturing processes, with local maximum magnitudes (ML) of M 1.6. The largest earthquake was located 7.6 km northwest of the active crater at a depth of 4.5 km. There were also recorded 461 events associated with fluid dynamics inside the volcanic edifice. Of these, 448 were classified as long-term (LP) events with reduced maximum displacement values (DRCs) of 7.3 cm2. Finally, 13 long-period events called « Tornillos » (TO) have been recorded, which are characterized by a quasi-homogeneous waveform in its spectral content and its long duration. The event with the highest energy had reduced displacement values of 2.6 cm2.

 

The images obtained from the cameras installed near the volcanic complex showed emission of fumaroles associated with steam from the active craters. The maximum height calculated was 200 meters above the craters. No explosive events were observed.
According to the data obtained from five (5) GNSS stations measuring the deformation of the volcano surface, no significant variation was observed. The lengths of control lines across the active craters showed variations less than 0.15 cm / month, suggesting that there are no relevant changes on the volcano. The data presented by the inclinometer suggest that there are no significant changes related to the morphology of the volcano.
No emissions of sulfur dioxide (S02) into the atmosphere in the volcano sector have been reported, according to data published by the Ozone Monitoring Instrument (IMO) Sulfur dioxide group (http: / / /so2.gsfc.nasa.gov/) and (NESDIS) (http://satepsanoine.nesdis.noaa.gov).
No thermal alerts were reported in the area associated with the volcano according to data processed by infrared, Mirova system (http://www.mirovaweb.it/) and MODVOLC (http://modis.higp.hawaii.edu/ ).

The volcanic complex exhibits a transitions behavior between explosive and non-explosive periods, which has been characteristic since this process began in 2016. During this period, volcanic activity parameters suggest that the interaction between the surface hydrothermal system  and magmatic activity decreased compared to the last period, which was characterized by the absence of explosions. However, given the dynamic behavior of the system, it is possible that the appearance of new explosions similar to those previously recorded or even stronger occur. Therefore, the technical volcanic alert remains:
YELLOW LEVEL: changes in the behavior of volcanic activity – probable time for an eruption: weeks / months.

Note: Due to the energy of the process, it is recommended to restrict access to the high-risk volcanic area, 3 km around the active craters.

 

Source : Sernageomin

 

Copahue , Chile :

During this period, seventy nine seismic events, twenty-one have been classified as events volcano – tectonic (VT) associated with rigid materials fracturing process were recorded. Similarly, fifty-eight events associated with fluid dynamics within the volcano, classified as long-term events (LP), with maximum displaced values (RDC) of 4.6 cm2 were recorded.
With regard to the VT-type seismic activity, the local magnitudes (ML) were less than or equal to M1.7. The most energetic event is located in the Northwest, 4.2 km from the Agrio crater with a depth of 2.7 km.

During this period, a constant amplitude constant tremor signal was recorded, mainly associated with the exit of the gases from the El Agrio crater. This signal has fluctuating reduced displacement values ​​(RDC) of the order of 3.0 +/- 0.5 cm2. The dominant frequencies are distinguished in two predominant bands, one marked at 0.6 Hz, and the other in a band between 1.1 and 1.7 Hz. The recording of point of increases in pulsatile character of a continuous tremor signal is distinguished, which can be associated with minor explosions at the crater, accompanied by emissions of ash. The acoustic signal associated with these phenomena is less than 0.6 Pascals, values ​​considered to be low.

According to the data obtained from three GNSS stations measuring the deformation of the volcano surface, small amplitude displacements for the horizontal and vertical components were observed. In turn, the control line through the volcano remained stable, while no changes were evident in the morphology of the volcano.
The IP cameras installed in the vicinity of the volcano showed a constant degassing of the active crater (El Agrio), with emissions predominantly of constant ash reported over several days, as well as sporadic incandescence. Most of the emission columns were directed to the southeast, with a maximum height of 1800 m.
Reconnaissance of July 10, with an overflight of the Agrio crater, found the presence of a cone of pyroclasts inside the crater and the continuous discharge of particulate matter that have largely deposited on the south-east side of the volcano . Thermal imaging temperatures do not exceed 200 ° C.

 

No emissions of sulfur dioxide (S02) into the atmosphere in the volcano sector have been reported, according to data published by the Ozone Monitoring Instrument (IMO) Sulfur dioxide group (http: / / /so2.gsfc.nasa.gov/) and (NESDIS) (http://satepsanoine.nesdis.noaa.gov).

No thermal alerts were reported in the area associated with the volcano according to data processed by infrared, Mirova system (http://www.mirovaweb.it/) and MODVOLC (http://modis.higp.hawaii.edu/ ).

The recording of a continuous tremor signal persists, which shows temporal variations in its amplitude and correlates with permanent and pulsatile degassing of particulate matter, causing incidents of nocturnal incandescence. Therefore, the interaction of a small amount of magma with the surface hydrothermal system feeds the explosive activity with emissions of materials limited to the crater.
Therefore, the technical alert level remains at:
YELLOW LEVEL: changes in the behavior of volcanic activity – probable time for a rash: weeks / months.

Note: It is recommended to apply preventive restrictions on the access of a zone near the crater with a radius of 1000 m, as the activity of fumaroles persists.

Source : Sernageomin

 

Piton de la Fournaise , La Réunion :

The eruption begun on July 14 at 00:50 local time continues. The intensity of the volcanic tremor (surface eruptive intensity indicator) has been relatively constant for more than 72 hours, with an intensity equivalent to that observed on the second day of the eruption (Figure 1). The slight variations in the last few hours are related, among other things, to the poor on-site weather conditions that sound seismic signals.

Figure 1: Evolution of RSAM (volcanic tremor and eruption intensity indicator) between 00:00 (20h UTC) on July 14th and 16h00 (12h00 UTC) on 20th July on the RVL seismic station, located on the flank South of the volcano. (© OVPF / IPGP)

– No earthquakes have been recorded this day.
– A slight deflation (deflation) is always observed at the top of the terminal cone.

 

L’image contient peut-être : nuit

Due to bad weather conditions, no field reconnaissance could be made today. Similarly, no estimate of flow could be made.

Source : OVPF

Photo : Christian Lesport.

 

Karymsky , Kamchatka :

54.05 N, 159.44 E;
Elevation 4874 ft (1486 m)
Aviation Color Code is ORANGE

A moderate eruptive activity of the volcano continues. Ash explosions up to 16,400-19,700 ft (5-6 km) a.s.l. could occur at any time. Ongoing activity could affect low-flying aircraft.

 

 

Explosive activity of Karymsky volcano on 18 July, 2017.

A moderate eruptive activity of the volcano continues. According to data by volcanologists, explosions sent ash up to 1.7 km a.s.l. on 18 July. Satellite data by KVERT showed a weak thermal anomaly over the volcano on 18-20 July; an ash cloud drifted for about 117 km to the east from the volcano on 20 July.

Source : Kvert

Photo : A. Belousov. IVS FEB RAS

 

Sabancaya , Peru :

The technical and scientific committee has reported columns of gas and ash up to 5,500 meters of altitude in recent weeks. The ash was dispersed within a radius of 50 km.

The explosive activity of the Sabancaya, according to the latest reports of the IGP Observatory and INGEMMET, remains moderate; However, the height of the ash columns caused by the explosions reached altitudes higher than 5 km, making them more visible from the districts to the south of the city of Arequipa.

 

Professionals from both institutions reported that explosions and subsequent dispersal of ash is noticeable in the districts of Sachaca, Tiabaya and Hunter. The clear vision of the current Sabancaya eruption is subject to cloud conditions, which in the last month limited observation and made it sometimes non-existent.

According to the Committee’s reports, about 20 daily explosions have been recorded, with the ashes dispersed within a radius of 50 km around the volcano. In recent days, these materials have fallen into the Colca valley due to prevailing winds in the region. « Ash dissemination alerts are continuously issued for populations in a range of 30 km to 50 km from the volcano. People should not neglect preventive measures to protect their health and integrity, « he said.

 

Résultat de recherche d'images pour "sabancaya arequipa"

Finally, they said that the current eruption of the Sabancaya is going through a period of high and low, which alternates according to the arrival of new magmatic material in the inner chamber of the volcano in its attempt to reach the surface. « We monitor this eruptive process permanently by seismic, geodetic, geochemical stations and real-time cameras. For a possible increase in activity, the Committee will immediately inform of this situation, « they said.

Source : IGP

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