Report on Turrialba (Costa Rica) — August 1992
Bulletin of the Global Volcanism Network, vol. 17, no. 8 (August 1992)
Managing Editor: Lindsay McClelland.
Turrialba (Costa Rica) Continued seismicity and fumarolic activity
Please cite this report as:
Global Volcanism Program, 1992. Report on Turrialba (Costa Rica). In: McClelland, L (ed.), Bulletin of the Global Volcanism Network, 17:8. Smithsonian Institution. https://doi.org/10.5479/si.GVP.BGVN199208-345070.
10.025°N, 83.767°W; summit elev. 3340 m
All times are local (unless otherwise noted)
Fumarole temperatures in the central crater were <=93.6°C during fieldwork by ICE geologists on 13 August, similar to observations in previous years. No changes in surface activity were evident. The UNA seismograph (VTU) 0.5 km E of the main crater recorded 14 low-frequency events in August.
Geologic Background. Turrialba, the easternmost of Costa Rica's Holocene volcanoes, is a large vegetated basaltic-to-dacitic stratovolcano located across a broad saddle NE of Irazú volcano overlooking the city of Cartago. The massive edifice covers an area of 500 km2. Three well-defined craters occur at the upper SW end of a broad 800 x 2200 m summit depression that is breached to the NE. Most activity originated from the summit vent complex, but two pyroclastic cones are located on the SW flank. Five major explosive eruptions have occurred during the past 3500 years. A series of explosive eruptions during the 19th century were sometimes accompanied by pyroclastic flows. Fumarolic activity continues at the central and SW summit craters.
Information Contacts: G. Soto and R. Barquero, ICE; E. Fernández, J. Barquero, and V. Barboza, OVSICORI.