Observatorio Vulcanológico del INGEMMET (OVI) reported that during a field inspection of Sabancaya on 25 August scientists noted five new fumarolic areas; two were located in the N part of the summit area, and three were on the NE flank. The number of hybrid earthquakes increased during 25-27 August. A small explosion at 0651 on 27 August produced a dense ash plume that rose 1 km above the crater and drifted E.

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: Observatorio Vulcanológico del INGEMMET (OVI)