Report on Llaima (Chile) — 13 August-19 August 2008
Smithsonian / US Geological Survey Weekly Volcanic Activity Report,
13 August-19 August 2008
Managing Editor: Sally Kuhn Sennert
Please cite this report as:
Global Volcanism Program, 2008. Report on Llaima (Chile). In: Sennert, S K (ed.), Weekly Volcanic Activity Report, 13 August-19 August 2008. Smithsonian Institution and US Geological Survey.
38.692°S, 71.729°W; summit elev. 3125 m
All times are local (unless otherwise noted)
During 8-11 August, SERNAGEOMIN reported that fumarolic activity from the snow-free pyroclastic cones in Llaima's main crater was visible during periods of clear weather; resultant plumes drifted E. A 2-km long strip on the NE flank was black in color (snow-free) due to elevated temperatures. On 13 August, gas-and-ash plumes rose to an altitude of 3.3 km (10,800 ft) a.s.l. and drifted E. Later that day, incandescence from the crater accompanied the gas-and-ash emissions.
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.