Instituto Geofísico del Perú (IGP) reported that moderate levels of eruptive activity continued at Sabancaya during 5-11 February. The monitoring network recorded a daily average of 33 explosions that often ejected gas-and-ash emissions as high as 2 km above the summit crater; ash plumes drifted less than 10 km downwind. The seismic network recorded seismic signals associated with the movement of magma and gases; counts ranged between 17 and 69 events per day. Thermal anomalies over the lava dome in the summit crater were identified in daily processed satellite data. Deformation monitoring data indicated slight inflation of the area near the Hualca Hualca sector (4 km N) continued. The Alert Level remained at Orange (the third level on a four-color scale) and the public was reminded to stay at least 12 km away from the summit crater in all directions.

Geological Summary. Sabancaya, located in the saddle NE of Ampato and SE of Hualca Hualca volcanoes, is the youngest of these volcanic centers and the only one to have erupted in historical time. The oldest of the three, Nevado Hualca Hualca, is of probable late-Pliocene to early Pleistocene age. The name Sabancaya (meaning "tongue of fire" in the Quechua language) first appeared in records in 1595 CE, suggesting activity prior to that date. Holocene activity has consisted of Plinian eruptions followed by emission of voluminous andesitic and dacitic lava flows, which form an extensive apron around the volcano on all sides but the south. Records of observed eruptions date back to 1750 CE.

Source: Instituto Geofísico del Perú (IGP)