Through an official statement, the Ministry of Mines and Energy as well as the Colombian Geological Service (SGC) alerted about the seismic activity associated with the fracturing of rock inside the volcanic edifice, informing that the volcano maintained similar levels compared to the previous day (14 of April).
The earthquakes were located in the eastern-northeastern and southwestern sectors of the volcano and in the Arenas crater, at depths between 0.5 and 4.5 km. The maximum magnitude was 0.8 corresponding to the earthquake at 12:49 am, located 1.1 km to the east-northeast of the crater, at a depth of 3.6 km.
On the other hand, the institution that monitors the changes of the Nevado del Ruíz volcano mentioned that the seismicity related to the movement of fluids inside the volcanic conduits associated with pulsatile ash emissions continued. Several of these ash emissions were confirmed through the web cameras used to monitor the volcano.
The maximum height of the column of gases and/or ash observed was 1600 m, measured from the top of the volcano, with a dispersion direction towards the northwest. Thermal anomalies continue at the bottom of the crater, which are observed from satellite platforms. Regarding the output of sulfur dioxide into the atmosphere, it maintained levels similar to the previous days.
John Mario Londoño, technical director of geothreats of the SGC insisted that the volcano’s activity for this Sunday, April 16, was still very unstable, which is why the orange alert is maintained:
“It is important to understand that the volcano is still very unstable and that it is necessary to continue monitoring the state of activity to review the parameters that up to now show that the volcano has not returned to normal levels of activity,” Londoño mentioned, adding that although the seismicity of fracture can vary and change location, the presence of thermal anomalies in the bottom of the crater greater than those presented in previous months, associated with the output -sometimes continuous- of ash, are parameters that indicate a higher level of activity of this with compared to previous weeks, which must be permanently and specially monitored.
The most significant eruption of the last 10 years
Likewise, Londoño asked the community in general to follow the indications and recommendations of the authorities since the Nevado del Ruiz volcano could erupt in days or weeks and that this would be the most significant eruption it has done in the last decade.
“To change the level and return to the yellow level, a prudential time is required where trends and patterns can be observed that allow us to infer the possible decrease in activity, which is why it is warned that the level of activity of the Nevado del Ruiz volcano will remain at ORANGE LEVEL for several weeks. During this time, in the event that there is an acceleration of the processes that suggest an imminent eruption or that the eruption itself occurs, the activity level will be changed to red”, mentions the official statement of the GSC.