Report on Llaima (Chile) — 27 May-2 June 2009
Smithsonian / US Geological Survey Weekly Volcanic Activity Report, 27 May-2 June 2009
Managing Editor: Sally Kuhn Sennert
Please cite this report as:
Global Volcanism Program, 2009. Report on Llaima (Chile). In: Sennert, S K (ed.), Weekly Volcanic Activity Report, 27 May-2 June 2009. Smithsonian Institution and US Geological Survey.
38.692°S, 71.729°W; summit elev. 3125 m
All times are local (unless otherwise noted)
SERNAGEOMIN reported that scientists aboard an overflight of Llaima on 1 June observed a 2-square-kilometer area with an elevated temperature on the E flank. Several small areas emitted gas and a small cone was forming about 800 m below the crater. They also saw an E-W trending fissure 200 m from the rim of the main crater that was about 300 m long. Brown ash and steam plumes were emitted from different areas of the fissure. The irregularly-shaped summit crater had a few weak fumaroles. The Volcano Alert Level remained at Yellow.
Geologic Background. 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.