On 2 September, SERNAGEOMIN reported that clouds had prevented visual observations of Llaima during the previous few days. Explosions were heard during 25-28 August. On 28 August, seismic signals indicated that gas-and-ash plumes were possibly emitted from the pyroclastic cones in the main crater. The Volcano Alert Level remained at Yellow.

Geological Summary. Llaima, one of Chile's largest and most active volcanoes, contains two main historically active craters, one at the summit and the other, Pichillaima, to the SE. The massive, dominantly basaltic-to-andesitic, stratovolcano has a volume of 400 km3. A Holocene edifice built primarily of accumulated lava flows was constructed over an 8-km-wide caldera that formed about 13,200 years ago, following the eruption of the 24 km3 Curacautín Ignimbrite. More than 40 scoria cones dot the volcano's flanks. Following the end of an explosive stage about 7200 years ago, construction of the present edifice began, characterized by Strombolian, Hawaiian, and infrequent subplinian eruptions. Frequent moderate explosive eruptions with occasional lava flows have been recorded since the 17th century.

Source: Servicio Nacional de Geología y Minería (SERNAGEOMIN)