Copahue volcano (March 16 to 31).
The level of activity of the volcano is at: Level YELLOW, changes in the behavior of volcanic activity -Time For a probable eruption weeks / months.
Based on the analysis of information obtained by monitoring equipment and surveillance of the volcano, the National Geology and Mining Service (SERNAGEOMIN) -Observatorio Volcanológico of Los Andes del Sur (OVDAS) announces:
During this period, fifty-four (54) seismic events were registered, twelve (12) were classified as volcano tectonic (VT) associated with rock fracturing process.
Similarly, forty-two (42) events associated with the fluid dynamics inside the volcano , twenty-nine of which (29) were identified as long-period earthquakes (LP) and thirteen (13) as events very long period (VLP) were recorded.
Regarding seismic activity type VT, the local magnitude (ML) are less or equal to M1,5. The most important energy event was located on the northeast side (NE) to 17.6 km of the El Agrio crater with a depth of 4.5 km.
Regarding LP type of events, they showed reduced displacements values (DRC) below 14,4cm2, the local magnitude (ML) was less than M1,9 and mostly situated around the crater.
Seismicity VLP has local magnitude (ML) lower to M1,8 and reduced displacement values (DRC) of 21,3cm2 maximum, mostly located around the crater with epicentral distances of less than 4,0 km.
Throughout the month, there was a constant tremor signal, mainly associated with particulate emissions (gases and ash) from the crater El Agrio, which reported reduced displacement values (DRC) oscillating around about 3 cm2, values considered as intermediate for this volcano. The dominant frequencies are concentrated in a bandwidth from 1.0 to 2.0 Hz.
From the data obtained from five (5) GNSS stations, which measure the deformation of the surface of the volcano, it is noted that the horizontal and vertical components have low amplitude variations. The maximum displacement rate is calculated at 0,19cm / month for the horizontal components and 0.25 cm / month for the vertical component.
In addition, the control line that crosses the volcano indicates a tendency to increase at a lower rate of 0.3cm / month, according to a slight inflation.
Sulfur dioxide emissions (SO2) recorded on the volcano Copahue by the team DOAS (Differential Optical Absorption Spectrometry) Triplets station, located 5 km to the east-northeast (ENE) of the active crater has experienced a mean value of 853 ± 189 t / day and a maximum value observed during the first two weeks of 2830 t / day, recorded on March 23. The average flow is considered at low levels for this volcano.
IP cameras installed near the volcano recorded the constant emission of material from the active crater (El Agrio)accompanied by night glows . These emissions are mostly characterized by a gray color, showing the presence of particulate matter.
The maximum height of the column was 1500 m observed on March 22.
The same pattern of activity of the volcano continues, linked to the interaction of a low volume of magma body at a level more or less deep into the volcanic edifice, with the surface hydrothermal system without unbalancing, keeping a metastable equilibrium. This activity may continue for a long time. No specific increase related to small phreatic explosions and / or low strombolian activity in the crater area is rejected. Therefore, is considered high risk zone that contained in a radius of 1.5 km around the crater el Agrio and therefore it is recommended to restrict access to this sector remaining at technical level of alert Yellow .
April 04 , 2016.Copahue , Chile :
Source : Sernageomin
Photos : Suyay Abou Adal , Volcanes Andinos .