THE JULY 1994 EPISODE OF SEISMIC ACTIVITY AT COLIMA VOLCANO, MEXICO

A new period of seismic activity that culminated in a small phreatic explosion took place in Colima Volcano (Western Mexico) during the month of July, 1994. In this note, we present our analysis of this seismicity based upon information from RESCO, the seismic network of the University of Colima. The activity began with a seismic swarm of type A (tectonic-like) earthquakes with epicenters towards the SSW of the summit, followed by shallow low-frequency events underneath the volcanic edifice. The activity was accompanied by landslides and culminated with an explosion that produced small ash falls on the surrounding area. The seismic activity ceased after this episode.