Activity level of the Nevado del Ruiz volcano.
The level of activity continues at : level of activity 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 an unstable behavior. The recorded seismic activity was mainly due to the fracturing of the rock in the volcanic structure. This type of seismicity has been located in areas: North, South, Southwest and in the Arenas crater at depths ranging between 1 and 5.2 km. The maximum magnitude recorded during the week was 1.7 ML (local magnitude), corresponding to an earthquake on December 2 at 00:50 (local time) near the Arenas crater at a depth of 2, 22 km.
Seismic activity associated with fluid dynamics in volcanic conduits, was characterized by recording type of LP earthquakes (long period) and episodes of volcanic tremor of short duration. Some of these events were associated with gas emissions and ash into the atmosphere, which could be verified by web cameras installed in the volcano area. Seismicity related to fluid circulation is located mainly in the Southeast sector and near the Arenas crater. The volcanic deformation measured from electronic inclinometers, navigation satellite systems (GNSS) and satellite images, which records changes in tilt, position and shape of the volcano (respectively) during the last period evaluated , did not show any major change.
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 900 meters above the summit of the volcano on 06 and 07 December . The direction of the dispersion of the column was in harmony with the wind regime, which during the week showed a predominant direction toward the northwest.
Although so far there has been no new episodes of signals called « drums« , associated with the rise of magma to the surface, it is considered that the system continues to evolve. New events can indicate an acceleration of the process, involve greater system instability and forces to alter the level of activity. It is essential to pay attention to official information to be published by the Colombian Geological Service. Therefore, we reiterate to the authorities in the departments of Caldas and Tolima the necessity of extreme vigilance, carried on the processes of reduction and vulnerability management and risk management activity of the Nevado del Ruiz volcano.
December 10, 2015. Nevado del Ruiz , Colombie :
Source : SGC.Gov.Co