Report on Turrialba (Costa Rica) — 16 November-22 November 2016
Smithsonian / US Geological Survey Weekly Volcanic Activity Report, 16 November-22 November 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, 16 November-22 November 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 that tremor and ash emissions at Turrialba ceased on 17 November. Tremor amplitude increased at 0140 on 19 November, though weather clouds prevented visual confirmation of correlating emissions. By 0800 tremor amplitude was low and some long-period events were recorded. Low emissions were mostly white, indicating gas, water vapor, and minor amounts of ash. A small quantity of ash fell in Cartago and Paraíso de Cartago (25 km SW). Tremor amplitude remained low on 20 November. A thin layer of ash deposits were reported in Ipis de Goicoechea, 27 km SW of the crater.
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.