Nevado del Ruiz volcano (Colombia), activity update: increase in shallow earthquakes under Arenas crater

From 12:30 hours local time on February 23, a new increase in seismic activity of the Nevado del Ruiz volcano began, characterized by the occurrence of shallow earthquakes associated with fluid movements and fracturing of rock. INGEOMINAS also measured increased SO2 emissions and some changes in strain measurements. 
So far, the energy level of this increase is low compared with previous episodes of unrest, but small eruptions in the near future are possible. 
The seismicity is located under the active Arenas crater at depths ranging between 0.5 and 3 km, and reached a maximum recorded magnitude of 1.4 on the Richter scale.

http://www.volcanodiscovery.com/view_news/5837/Nevado-del-Ruiz-volcano-Colombia-activity-update-increase-in-shallow-earthquakes-under-Arenas-crater.html