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
-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.
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.
January 02 , 2016. Nevados de Chillan , Chile :
Source : Sernageomin , GVP.
Photos : lostraviajadores .