Report on Villarrica (Chile) — 10 December-16 December 2014
Smithsonian / US Geological Survey Weekly Volcanic Activity Report,
10 December-16 December 2014
Managing Editor: Sally Kuhn Sennert
Please cite this report as:
Global Volcanism Program, 2014. Report on Villarrica (Chile). In: Sennert, S K (ed.), Weekly Volcanic Activity Report, 10 December-16 December 2014. Smithsonian Institution and US Geological Survey.
39.42°S, 71.93°W; summit elev. 2847 m
All times are local (unless otherwise noted)
According to Projecto Observación Visual Volcán Villarrica (POVI), satellite images of Villarrica acquired on 10 and 26 November and 3 December revealed a progressively more intense thermal anomaly. Photographs on 9 December showed particulates suspended above the crater rim, and the next day a thin veneer of ash covered the NW edge of the crater rim. Detonations from the crater were heard during 10-12 December. On 13 December observers noted that the intense blasts of gas from the previous few days had removed some ash deposits from the inner crater wall leaving lighter colored streaks.
Geological Summary. Glacier-clad Villarrica, one of Chile's most active volcanoes, rises above the lake and town of the same name. It is the westernmost of three large stratovolcanoes that trend perpendicular to the Andean chain. A 6-km-wide caldera formed during the late Pleistocene. A 2-km-wide caldera that formed about 3500 years ago is located at the base of the presently active, dominantly basaltic to basaltic-andesitic cone at the NW margin of the Pleistocene caldera. More than 30 scoria cones and fissure vents dot 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. Historical eruptions, documented since 1558, 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.