Report on Turrialba (Costa Rica) — 29 June-5 July 2016
Smithsonian / US Geological Survey Weekly Volcanic Activity Report,
29 June-5 July 2016
Managing Editor: Sally Kuhn Sennert
Please cite this report as:
Global Volcanism Program, 2016. Report on Turrialba (Costa Rica). In: Sennert, S K (ed.), Weekly Volcanic Activity Report, 29 June-5 July 2016. 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 increased tremor at Turrialba that began at 2125 on 28 June, likely coinciding with a gas-and-ash emission. Another signal at 2159 also likely coincided with an ash emission. No activity was observed with the webcam, although it was dark and cloudy. Activity had significantly decreased by 0800 on 30 June. Seismicity remained low through 5 July with only a few low-frequency earthquakes detected. Gas emissions were mostly comprised of water vapor.
Geological Summary. 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.