January 02, 2016 . EN. Nevados de Chillan , Nevado Del Ruiz, Sheveluch .

Home / blog georges Vitton / January 02, 2016 . EN. Nevados de Chillan , Nevado Del Ruiz, Sheveluch .

January 02, 2016 . EN. Nevados de Chillan , Nevado Del Ruiz, Sheveluch .

January 02 , 2016.

 

Nevados de Chillan , Chile :

 

Nevados de Chillan volcanic complex (1 to 31 December).
The level of activity of the volcanic complex is amended as follows:
YELLOW LEVEL: Changes in the behavior of volcanic activity
Time for a probable eruption:
Weeks / months.

Based on the analysis of information collected by the monitoring equipment and the volcanic complex monitoring, the National Geology and Mining Service (SERNAGEOMIN) Volcanological Observatory of the southern Andes (OVDAS), announces:


– It was installed two (2) new seismic stations and three (3) GPS stations with real-time transmission, improving complex monitoring network.
– It was recorded 1259 (1259) seismic events, including one hundred eighty-six (186) were related to fracturing processes of a rigid material, called volcano tectonic earthquakes (VT) with maximum local magnitude ( ML) of 1.8.
. The earthquake of greater magnitude was located at 17 km North – North – West (NNW) of the crater, at a depth of 4 km. In addition, thirty thousand (1030) earthquakes associated with fluid dynamics inside the volcano, called long-period events (LP) with a lower or equal amplitude (ML) of 1.7, with a reduced displacement (DRC ) of 61cm2 and forty (40) short spasmodic episodes of tremor and three (3) Tornillo type events (TO) were recorded.
Most locations of earthquakes, both LP and VT were concentrated around the southern cone of the complex, at depths of less than 5 km.
-The Image of IP cameras installed in the northwest (NW) of the complex showed a white plume December 9

nevado chillan
-The Data provided by the two (2) electronic inclinometers and new GPS stations that control the deformation of the volcanic complex,  showed no change due to the internal activity of the volcano during this period.
-The Images published by the OMI (Ozone Monitoring Instrument, sulfur dioxide Group (http://so2.gsfc.nasa.gov/) and NESDIS (National Environmental Satellite, Data, and Information , IMO Group http: // sateps anone.nesdis.noaa.gov) ‘reported no abnormal emissions of sulfur dioxide (SO2) into the atmosphere in the area near the volcanic complex.
-The Thermal radiation released by the MODVOLC (Moderate Resolution Imaging Spectroradiometer) MODIS on its website (http://modis.higp.hawaii.edu/) and Mirova (Middle InfraRed Observation of volcanic activity) on its website ( http: / /www.mirovaweb.it/) tracking system indicating significant changes in surface temperature,  reported no heat alert in the area associated with the volcanic complex.


Comments mountaineers during the ascent of the month, described the increased volcanic gas emissions, through new openings and an increase in surface temperature, compared to previous years. Monitoring parameters indicate changes in volcanic activity, showing a gradual increase in the number of events, indicating increased activity of deep hydrothermal system, may be affected by an increase in heat flow of magma system in depth.
It has not yet been recorded activity that may be related to a magmatic intrusion significant at shallow levels of the volcano. However, volcanic activity at its basic level, has been an increasing trend for three consecutive months. Therefore Technique alert level is changed to: LEVEL YELLOW.
He stressed that the volcanic system is not yet in a state of obvious imbalance and therefore there is no volcanic risk.

P1000431

The compound volcano of Nevados de Chillán is one of the most active of the Central Andes of Chile. Three late-Pleistocene to Holocene stratovolcanoes were constructed along a NNW-SSE line within three nested Pleistocene calderas, which produced ignimbrite sheets extending more than 100 km into the Central Depression of Chile. The largest stratovolcano, dominantly andesitic, 3212-m-high Cerro Blanco (Volcán Nevado), is located at the NW end of the group, and 3089-m-high Volcán Viejo (Volcán Chillán), which was the main active vent during the 17th-19th centuries, occupies the SE end. The new Volcán Nuevo lava-dome complex formed between 1906 and 1945 between the two volcanoes and grew to exceed Volcán Viejo in altitude. The Volcán Arrau dome complex was constructed SE of Volcán Nuevo between 1973 and 1986, eventually exceeding its height by 20 m.

 

Source : Sernageomin , GVP.

Photos : lostraviajadores .

 

 

Nevado Del Ruiz, Colombia :

 Weekly Bulletin of Activity of the volcano Nevado del Ruiz, from 22 to 28 December, 2015
Subject: internal activity of the Nevado del Ruiz volcano.
The level of activity continues at :  activity level Yellow or (III): changes in the behavior of volcanic activity.


Regarding the monitoring of the activity of the Nevado del Ruiz volcano, the SERVICIO Geologico COLOMBIANO reports:

During the last week, the volcanic system continued to show unstable behavior. The recorded seismic activity was mainly associated with fluid dynamics in volcanic conduits. This type of seismicity, was characterized by the appearance of continuous tremors and type of long period earthquakes (LP), located mainly in the vicinity of Arenas crater and in the Southeast region of the volcano. Two episodes of continuous volcanic tremors recorded between 20 and 25 December 2015 whose presence was reported by extraordinary bulletin had a lower power level since the same evening until morning, indicating variability the volcanic system. Do not rule out that he could present new episodes of this signal, which is associated with the emission of gases and ash in the atmosphere, which can be dispersed in accordance with the system of winds blowing in the region.

 

nevado


As for seismic activity related to the fracturing of the rock in the volcanic structure, this type of seismicity was located mainly in North-distal zones, Southwest, South and South-East of the Arenas crater and, a lesser extent around the crater. The depth of the earthquake was between 1,05 and 7,66 kilometers. The maximum magnitude recorded during the week was 1.4 ML (local magnitude), corresponding to an earthquake on December 28 at 14h57 (local time) 7 km north of Arenas crater at a depth of 5, 39 km.

The volcanic deformation measured from electronic inclinometers, global navigation satellite systems (GNSS) and satellite images, which record changes in tilt, position and shape of the volcano (respectively) during the last period evaluated, did not show significant changes.
The volcano continues to emit into the atmosphere large quantities of steam of water and gas, including sulfur dioxide (SO2) which is characterized, as has been estimated by the permanent stations SCAN DOAS installed on the area the volcano and satellite imagery.


The column of gas, steam and ash reached a height of 1700 meters above the summit of the volcano on December 28. The direction of the dispersion of the column is in line with the regime of prevailing winds in the region, who, during the week showed a predominant direction toward the northwest over the volcano.

With satellite images for monitoring provided by the Italian universities of Turin and Florence (portal Mírová) and the University of Hawaii (MODVOLC) thermal anomalies were recorded on the volcano on 22, 23, 24 and 26 December .

It is considered that the volcanic system continues to evolve and new events may indicate an acceleration of the process. By involving greater instability thereof, changes in activity level may occur. It is essential to pay attention to official information to be published by the SERVICIO Geologico COLOMBIANO.

Source : SGC

 

 

Sheveluch, Kamchatka :

56.64 N, 161.32 E;
Elevation 10768 ft (3283 m),
the dome elevation ~8200 ft (2500 m)
Aviation Color Code is ORANGE

Explosive-extrusive eruption of the volcano continues. Ash explosions up to 32,800 ft (10 km) a.s.l. could occur at any time. Ongoing activity could affect international and low-flying aircraft.
sheveluch

Ash plume rose up to 5.5 km a.s.l. when a hot avalanche collapsed from western flank of the lava dome of Sheveluch. Ash plume extended to the south-east of the volcano.

A growth of the lava dome continues (a viscous lava block extrude in the northern its part), fumarole activity, ash explosions, hot avalanches and an incandescence of the dome blocks and hot avalanches accompany this process. According to video data, an incandescence of the dome lava blocks and moderate hot avalanches were observing all week. The hot avalanche collapsed from western flank of the lava dome on 31 December, an ash plume rose up to 5.5 km a.s.l. and extended about 50 km to the south-east of the volcano. Satellite data by KVERT showed an intensive thermal anomaly over the lava dome all week.

Source : Kvert

Photo : Yu. Demyanchuk. IVS FEB RAS, KVERT

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