Bulletin activity of the volcano Nevado del Ruiz, 1 to 7 March 2016
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, the SERVICIO Geologico COLOMBIANO reports:
During the last week, the volcanic system continued to show unstable behavior. The recorded seismic activity was mainly associated with fluid dynamics in volcanic conduits, and was characterized by the occurrence of earthquakes long period (LP) and short volcanic tremor pulses with significant levels of energy , some of them associated with ash emissions. Continued episodes of tremor were also recorded. These seismic signals were mainly located near the Arenas crater and in the South and Southeast areas of the volcano. These processes were accompanied by thermal anomalies, which were identified by monitoring the satellite images provided by different agencies. A weak thermal anomaly on March 6, was identified near the Arenas crater, confirming the instability of the Nevado del Ruiz volcano and corroborates that the process continues to evolve.
Seismic activity related to the fracturing of the rock in the volcanic structure is mainly located in the North and North-distal sectors and, to a lesser extent, scattered in the North-East areas, South East of the Arenas crater and close to the crater. The depth of the earthquake was between 1.19 km and 7.43 km. The largest seismic event of the week was 1.7 M (locally) on March 5 at 17h02 (local time), located in the distal part of the North sector compared to the Arenas crater at a depth of 6.42 km.
The volcanic deformation measured from electronic inclinometers, global navigation satellite systems (GNSS) and satellite images, which record changes in the tilt, the position and shape of the volcano (respectively) during the last evaluation period continues to make changes.
The volcano continues to emit into the atmosphere large amounts of steam and water gas, including sulfur dioxide (SO2), as has been estimated by the permanent stations SCAN DOAS installed in the Volcano area and on satellite imagery.
The column of gas, steam and ash reached a maximum altitude of 3,000 meters above the volcano’s summit on March 3. 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 northwest over the volcano.
March 10, 2016. Nevado Del Ruiz , Colombia :
Source : SGC.Gov.Co
Photos : SGC.