During the month of August Nevado Del Ruiz volcano in Columbia was showing abundant signs of life and it’s status has been raised to yellow (3) as it continues to exhibit changes in activity. There are no web-accessible seismographs on Ruiz so we have to depend on what comes out of Columbia for our information.
Ruiz is best known for it’s 1985 eruption which produced the lahars that wiped out the towns of Armero and Chinchina killing more than 24,000 people
Activity at Ruiz during August included 1091 seismic events, 399 of which had to do with breaking rock in the active crater and to the southeast. 692 quakes recorded during August were associated the the movement of magma within and beneath the volcanic edifice, and there were minor signals associated with small phreatic explosions.
On August 21st a 900 meter column of gas was observed. No deformation of the mountain has been detected. Ruiz is fully instrumented with seismographs, inclinometers, and magnetometers. I’ll try to keep you updated on this one, but I really have to dig for information on Ruiz.
Cerro Machin Volcano is also at yellow (3) status for changes in volcanic activity.