Report on Antuco (Chile) — 24 April-30 April 2013
Smithsonian / US Geological Survey Weekly Volcanic Activity Report,
24 April-30 April 2013
Managing Editor: Sally Kuhn Sennert
Please cite this report as:
Global Volcanism Program, 2013. Report on Antuco (Chile). In: Sennert, S K (ed.), Weekly Volcanic Activity Report, 24 April-30 April 2013. Smithsonian Institution and US Geological Survey.
37.406°S, 71.349°W; summit elev. 2979 m
All times are local (unless otherwise noted)
The Buenos Aires VAAC reported that only gas and steam rose from Antuco on 20 April; although a pilot reported ash emissions, ash was not identified in satellite imagery or by web camera during clear skies.
Geological Summary. Antuco volcano, constructed NE of the Pleistocene Sierra Velluda stratovolcano, rises dramatically above the SW shore of Laguna de la Laja. It has a complicated history beginning with construction of the basaltic-to-andesitic Sierra Velluda and Cerro Condor stratovolcanoes of Pliocene-Pleistocene age. Construction of the Antuco I volcano was followed by edifice failure at the beginning of the Holocene that produced a large debris avalanche which traveled down the Río Laja to the west and left a large 5-km-wide caldera breached to the west. The steep-sided modern basaltic-to-andesitic cone has grown 1,000 m since then; flank fissures and cones have also been active. Moderate explosive eruptions were recorded in the 18th and 19th centuries from both summit and flank vents, and lava flows have traveled into the Río Laja drainage.