According to Projecto Observación Visual Volcán Villarrica (POVI), satellite images of Villarrica acquired on 25 July revealed a weak thermal anomaly. On 29 July observers photographed the crater and described a thermal anomaly on the S edge of the crater rim, in the same area from which a lava flow originated on 29 December 1971. They also heard deep degassing sounds. A second photograph showed a diffuse gas plume rising from the bottom of the crater, and ash and lapilli on the snow on the inner crater walls.

Geological Summary. The glacier-covered Villarrica stratovolcano, in the northern Lakes District of central Chile, is ~15 km south of the city of Pucon. A 2-km-wide caldera that formed about 3,500 years ago is located at the base of the presently active, dominantly basaltic to basaltic-andesite cone at the NW margin of a 6-km-wide Pleistocene caldera. More than 30 scoria cones and fissure vents are present on the flanks. Plinian eruptions and pyroclastic flows that have extended up to 20 km from the volcano were produced during the Holocene. Lava flows up to 18 km long have issued from summit and flank vents. Eruptions documented since 1558 CE have consisted largely of mild-to-moderate explosive activity with occasional lava effusion. Glaciers cover 40 km2 of the volcano, and lahars have damaged towns on its flanks.

Source: Proyecto Observación Villarrica Internet (POVI)