According to the daily bulletin of the Colombian Geological Service (SGC), the seismic activity associated with the fracturing of rock inside the volcanic edifice increased in the number of earthquakes and in seismic energy.
The earthquakes were located mainly approximately 3 and 4 km away to the west-northwest of the Arenas crater, at depths ranging between 4 and 5 km.
In this sense, the maximum magnitude registered was 1.0 corresponding to the earthquake registered at 01:37 pm, located 3.7 km to the west-northwest of the Arenas crater, at a depth of 5 km from the top of the volcano. . Small earthquakes were also recorded, although to a low extent, in the Arenas crater, which are associated with the activity of the lava dome (bulge or mound) located at the bottom of the crater.
On the other hand, the SGC informed the community that the seismic activity related to the movement of fluids inside the volcanic conduits showed similar levels in the number of earthquakes and in the seismic energy released, compared to May 31. Some of the seismic signals were associated with pulsatile ash emissions confirmed through the web cameras used for volcanic monitoring.
Regarding surface activity, the maximum height of the gas and/or ash column was 900 m measured from the top of the volcano and it continued to show a preferential direction of dispersion towards the northwest of the volcanic edifice. Additionally, the degassing of sulfur dioxide (SO2) and the release of water vapor from the crater to the atmosphere are maintained.
Satellite detection of significant thermal anomalies at the bottom of the crater indicates the presence of very hot material near the surface. Likewise, the recurrence of ash output, sometimes pulsatile and sometimes more continuous, the persistence of a slight deformation of the terrain, and the variations in the output of sulfur dioxide, indicate that the volcano could still make an important eruption in days or weeks.
Therefore, from the Geological Service they reiterate that the activity of the Nevado del Ruiz volcano continues at ORANGE LEVEL, which indicates that there is a probability that in days or weeks it will erupt more than it has in the last 10 years.