June 2015 – CHILE – Guallatiri or Guallatire is one of the most active volcanoes in northern Chile. It is just west of the border with Bolivia and at the southwestern end of the Nevados de Quimsachata. It is a symmetrical 6,071-metre-high (19,918 ft) (3.7723 miles) ice-clad stratovolcano. Wallatiri is capped by a central dacitic dome or lava complex, with the active vent at its southern side. The volcano last erupted in 1960. -Wikipedia
Elevated seismic activity since the night 30-31 May triggered SERNAGEOMIN to raise the alert level of the volcano to “yellow.” A swarm 22 earthquakes related to internal rock fracturing, possibly caused by rising magma, was registered shortly after midnight 30-31 May. A magnitude 3.7 quake occurred at 05:17 local time the next morning.
At the same time, slight deformation of the summit area of the volcano was detected as well, which would be consistent with a new magma intrusion at depth. No other changes (such as increased degassing, rock falls etc) have been noted. – Volcano Discovery