Poás Volcano | John Seach


Costa Rica

10.20 N, 84.23 W
summit elevation 2708 m

Poás is one of Costa Rica's most active volcanoes. The volcano is located within the Poas Volcano National Park.
It has been formed from adjoining eruptive centres with large collapse craters.

A famous eruption in 1910 sent a water geyser 4000 m into the air. Sulphur eruptions have occurred intermittently at the volcano since 1989.

2011 Earthquake
On 13th May 2011 there was a large (magnitude 6.0) earthquake 10 km south of Poas volcano. The focus was at a depth of 70 km.

2011 Phreatic Eruption
A small phreatic eruption occurred from a summit lake of Pos volcano on 2nd February. Material was ejected 6 m high. Bubbles of gas and upwelling sediments were observed from the lake surface.

2010 Phreatic eruption
A phreatic explosion occurred at Poas volcano on 23rd February at Laguna Caliente. Sulphurous deposits were ejected onto the southern flank. The event was not preceded by seismic activity.

2009 Earthquake and Eruption
A large earthquake (mag 6.1) occurred at Poas volcano on Thursday 8th January 2009. The epicentre was located 8 km east of the volcano summit. A phreatic eruption occurred at the summit lake (Laguna Caliente). The eruption ejected ash and steam 600 m above the lake.

2008 Eruption
A small phreatic eruption occurred at the crater lake (Laguna Caliente) on 13th January 2008. Ash was emitted to 2.0 km altitude, and forced the evacuation of 20 people.

2006 Eruptions
On 24th March 2006 eruptions occurred from the bottom of Caliente Lake. Two phreatic eruptions occurred at the crater lake on 25-26 September 2006. A phreatic eruption occurred on 16th December 2006. Erupted material reached a height of 30 m.

Further reading
Rowe Jr, G.L., Brantley, S.L., Fernandez, M., Fernandez, J.F., Borgia, A. and Barquero, J., 1992. Fluid-volcano interaction in an active stratovolcano: the crater lake system of Poás volcano, Costa Rica. Journal of Volcanology and Geothermal Research49(1-2), pp.23-51.

Oppenheimer, C. and Stevenson, D., 1989. Liquid sulphur lakes at Poás volcano. Nature342(6251), pp.790-793.

Casertano, L., Borgia, A., Cigolini, C., Morales, L.D., Montero, W., Gomez, M. and Fernandez, J.F., 1987. An integrated dynamic model for the volcanic activity at Poás volcano, Costa Rica. Bulletin of volcanology49(4), pp.588-598.

Poás Volcano Eruptions

2019, 2017, 2016, 2008-2011, 2006, 1996, 1994, 1992-93, 1992, 1991, 1991, 1987-90, 1981, 1980, 1979-80, 1978, 1977-78, 1977, 1976, 1974-75, 1972-73, 1970, 1969, 1967, 1964-65, 1963, 1958-61, 1952-57, 1948-51, 1946, 1941-46, 1929, 1925, 1914-15, 1914, 1910, 1910, 1907, 1898-91, 1880, 1879?, 1860, 1838, 1834, 1828.