IGP reported that on 6 August there was increasing seismic and fumarolic activity at Sabancaya over the past four days. Fumarolic emissions increased, were white to blueish white and gray and rose to 3 km above the crater. On 9 August IGP reported an explosion that lasted 50 seconds at Sabancaya accompanied by increasing seismic activity including a strong increase in hybrid earthquakes. Intermittent views in cloudy conditions showed strong fumarolic emissions continued.

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)