Report on Turrialba (Costa Rica) — 10 March-16 March 2010
Smithsonian / US Geological Survey Weekly Volcanic Activity Report, 10 March-16 March 2010
Managing Editor: Sally Kuhn Sennert
Please cite this report as:
Global Volcanism Program, 2010. Report on Turrialba (Costa Rica). In: Sennert, S K (ed.), Weekly Volcanic Activity Report, 10 March-16 March 2010. Smithsonian Institution and US Geological Survey.
10.025°N, 83.767°W; summit elev. 3340 m
All times are local (unless otherwise noted)
OVSICORI-UNA reported that scientists visited Turrialba at night on 7 March. A gas plume, commonly seen drifting with prevailing winds, was seen that night rising 1.5 km above the crater and drifting NW. Noises from the crater were described as sounding like a jet engine and rumblings. A vent, formed in January, emitted gas at temperatures between 300 and 320 degrees Celsius. Small blocks 3-12 cm in diameter and different colors dominated the surface around the vent. Lithics ejected 30-50 m away from the vent measured 170 degrees Celsius. Incandescence seen at night originated from the vent which ejected reddish-colored tephra.
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.