Internal activity level of the Nevado del Ruiz volcano.
The activity continues at 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 due to the fracturing of the rock in the volcanic structure. This type of seismicity was located in an area in the northeast, southwest and north of the volcano and the Arenas crater. The depths of between 0.9 and 7.1 kilometers. The maximum magnitude recorded during the week was 2.0 ML (local magnitude), corresponding to an earthquake on December 13 at 3:20 (local time), located north of Arenas crater at a depth of 3.6 km .
Seismic activity associated with fluid dynamics in volcanic conduits, was characterized by the recording of LP type earthquakes (long period) and episodes of volcanic tremor of short duration, which are linked to emissions of ash in the atmosphere. This seismicity induced by fluid movement is mainly located in the southeast sector of the Arenas crater and next to this one. 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) in the last evaluated period, showed no significant changes.
The volcano continues to emit into the atmosphere of significant amounts of water vapor and gases, including sulfur dioxide (SO2). The column of gas, steam and ash reached a height of 800 meters above the summit of the volcano on December 14. 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.
Although so far there have been no new episodes of signals called « drumbeat« , associated with the rise of magma to the surface, it is considered that the system continues to evolve and new events may indicate acceleration of the process. Which will involve greater volatility in the system and modify accordingly the level of activity. It is essential to pay attention to official information to be published by the SERVICIO Geologico COLOMBIANO.
December 18, 2015. Nevado Del Ruiz , Colombia :
Source : SGC