Report on Llaima (Chile) — 10 February-16 February 2010
Smithsonian / US Geological Survey Weekly Volcanic Activity Report,
10 February-16 February 2010
Managing Editor: Sally Kuhn Sennert
Please cite this report as:
Global Volcanism Program, 2010. Report on Llaima (Chile). In: Sennert, S K (ed.), Weekly Volcanic Activity Report, 10 February-16 February 2010. Smithsonian Institution and US Geological Survey.
38.692°S, 71.729°W; summit elev. 3125 m
All times are local (unless otherwise noted)
Cameras operated by OVDAS-SERNAGEOMIN showed steam-and-gas plumes rising from Llaima's main crater during 20 January-9 February. Seismic signals (tremor and volcano-tectonic earthquakes) had characteristics that indicated fluid movement within the volcano's conduits. The Alert Level was raised to Yellow, Level 3. SERNAGEOMIN recommended that people stay at least 4 km away from the main crater.
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.