June 09 , 2016. EN. Nevado Del Ruiz , San Miguel , Piton de la Fournaise , Pacaya , Fuego .
June 09 , 2016.
Nevado Del Ruiz , Colombia :
Subject: Activity Bulletin 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 last week, the seismic activity of the volcano Nevado del Ruiz presented mostly events related to fracturing of the rock inside the volcano. Earthquakes are located primarily in the distal seismogenic sources from the North, West, South North and to a lesser extent in the proximal part of the West, North and East compared to the crater Arenas and in the crater itself. The depths of the earthquakes were between 1.0 and 9.4 kilometers. The largest seismic event of the week was 2.5 ML (local Magnitude) recorded on June 3 at 0:49 (local time), located 2.4 km northeast of the Arenas crater at a depth of 3, 52 km.
Seismic activity associated with fluid dynamics in volcanic conduits, characterized by the appearance of long period earthquakes (LP) and very long period (VLP), as well as episodes of continuous volcanic tremor, low level energy, were also recorded, with pulses of tremor with varying energy levels. Some of these signals are associated with the gas and ash emissions. These events were mainly located in the southeast sector of the volcano and near the Arenas crater. The registration of new seismic signals of this type with high levels of energy and emissions of ash in the atmosphere are not excluded, which can be dispersed by the wind conditions prevailing in the region.
The volcanic deformation measured from electronic inclinometers, global navigation satellite systems (GNSS) and satellite images to track changes in the tilt, the position and shape of the volcano, respectively, continued to record Changes.
The volcano continues to emit into the atmosphere large amounts of steam and water gas, including sulfur dioxide (SO2), which is distinguished as it was estimated by the permanent stations SCANDOAS installed in the region of the volcano and satellite imagery.
In the monitoring of satellite images provided by the portal Mirova it was identified a level of thermal anomaly of low energy near the Arenas crater, June 5, this during the week. The persistence of these anomalies confirms the instability of the Nevado del Ruiz volcano and confirmed that the volcanic process continues to evolve.
The column of gas, steam and ash reached a height of 1800 m, measured from the top of the volcano, on May 31 The direction of the dispersion of the column was in line with the prevailing wind in the area, which during the week showed a predominant direction towards the southwest of the volcano.
Source : SGC
San Miguel ( Chaparrastique) , El Salvador :
Elevation 2130 m
SNET reported that between 13h04 and 14h30 on 31 May seismic signals at San Miguel increased, and indicated rock fracturing at depth and possible gas-and-ash emissions. Though weather clouds partially covered the volcano, the webcam recorded some pulses of gas emissions. Seismicity decreased the next day.
Special Report No. 3
The Chaparrastique volcano presents a significant decrease in seismic vibrations
Date and time of publication: 06/08/2016 10:30:00
Since 10h00 Monday, June 6, the values of the energy of the seismic tremor of Chaparrastique volcano began a downward trend and remained fluctuating between 55 and 58 units RSAM. In the last 24 hours seismic vibrations fluctuated between 44 and 64 units RSAM hour on average, with an average of 57 units, the maximum threshold of normal behavior RSAM is 150 units.
Figure 1. Behaviour of seismic tremor of the volcano from January 2016 until now.
Captured by the webcam installed on the hill El Pacayal, weather images show cloud cover that prevents to observe the crater.
Data show that the internal system of the volcano returned to a new stage of relaxation. However, the behavior of volcanic activity that showed the Chaparrastique above indicates that these relaxation periods are usually followed by drastic changes in some occasions, ended with low ash emissions or periods of strong degassing, this being the typical behavior of an active volcano.
MARN continues its enhanced surveillance, maintains close communication with the General Directorate of Civil Protection and local observers.
MARN invites journalists and people not to approach the summit of the volcano, because of the degree of danger it presents.
Source : GVP , Marn.
Piton de la Fournaise , La Réunion :
Activity Bulletin Wednesday, June 8, 2016
Since the end of the eruption OVPF recorded a total of :
22 volcano-tectonic earthquakes summital (including 1 June 1st, 3 June 6th 3 June 7th);
3 deep earthquakes beneath the Fournaise (between -10 and -15 km);
11 local earthquakes (Under the Island);
6 teleseismic (world, experienced by devices on the island);
200 collapses (in the crater Dolomieu and on the flows of August 2015).
Inflation continues at a still higher rate (more than 2 cm distance measured at the base of the terminal cone from the end of the eruption) which is equivalent to the rates prior to the eruption of August 2015.
A source of pressure was modeled ~ 1.5km below the summit.
Geochemistry of gas
Using its network of sensors the OVPF recorded:
at the top – Multigas station: no remarkable variation, the sulfur species remain generally low concentration, increases are punctual,
from the edge of the Enclos – NOVAC station network: the flow of SO2 below the detection threshold,
in the plain des Sables – measures CO2_sol by mobile device: latest measures this morning at Gite show a further increase,
from the Plains – CO2_sol stations: from 1 to 3 June was a significant increase in the Plaine des Palmistes
Alert level: Vigilance
Synthesis and Conclusion:
Seismicity is low
The deformation is important
The CO2 flux of soil are important
For the record, the last three eruptions (in July 2015, August 2015 and May 2016) the return of seismicity made themselves very late (maximum 2 weeks) as compared to other indicators.
Source : OVPF
Pacaya , Fuego , Guatemala :
Activity type Strombolian
Morphology: composite Stratovolcano
Geographical location: 14 ° 22’50 « N Latitude; 90 ° 36’00 » W. Longitude
Atmospheric conditions: Partly cloudy
Blue color expulsions and low white fumaroles are observed. Degassing product , this plume is of low height and is moving northeast.
Seismic station PCG reported an internal tremor associated with a degassing and increased low explosions.
During the evening hours, it was possible to observe a faint glow.
No impacts or rumbling sounds are reported.
Activity type vulcanian
Morphology: composite Stratovolcano
Geographical location: 14 ° 28’54 « N Latitude; 90 ° 52’54 » W. Longitude
Wind: Northeast, 3km / h
Maintains white degassing fumaroles at a height of about 4100 meters (13.451 feet) propagating towards the West and the South West
It was recorded 1-2 moderate explosions per hour, with a gray column of a height of 4400-4800 meters (14.435 to 15.748 feet), traveling 10 kilometers to the Southwest, West, North -West and North East.
These explosions have generated weak rumbling and ash falls in areas of Morelia, Hagia Sophia, Panimaché I and II, and the areas of the North East flank.
Source : Insivumeh
Photo : Rolfcosar, National Geographic