Poas Volcano

Updated: May 21, 2024 13:08 GMT - refresh

Stratovolcano 2708 m (8,884 ft)
Costa Rica, 10.2°N / -84.23°W
Current status: minor activity or eruption warning (3 out of 5)

Last update: 18 May 2024 (Volcanic Ash Advisory)

Poás is one of Costa Rica´s most active volcanoes, and one of its most frequently visited and prominent ones. It contains a green acid crater lake and during some of its frequent phreatic eruptions, water from the lake is ejected like a geyser.

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Typical eruption style: Phreatic eruptions, sometimes geyser-like ejections of water from the acid crater lake.
Poas volcano eruptions: 1828, 1834, 1838(?), 1860, 1879(?), 1880, 1888-91, 1895, 1898-1907, 1910, 1910, 1914, 1914-15, 1925, 1929, 1941-46, 1948-51, 1952-57, 1958-61, 1963, 1964-65, 1967, 1969, 1970, 1972-73, 1974-75, 1976, 1977, 1977-78, 1978, 1979-80, 1980, 1981, 1987-90, 1991, 1992, 1992-93, 1994, 1996, 2010, 2011, 2012, 2013, 2014, 2016, 2017

Latest nearby earthquakes

Time	Mag. / Depth	Distance / Location
May 18, 09:25 pm (Costa Rica)	2.7 9 km	24 km (15 mi) to the E	Costa Rica: 12 km al Suroeste de Horquetas, Sarapiqui. I FELT IT - 1 report	Info
Sunday, May 12, 2024 GMT (1 quake)
May 12, 08:10 am (Costa Rica)	2.5 78 km	8.9 km (5.5 mi) to the SE	6 Km al suroeste de Vara Blanca, Costa Rica	Info
Saturday, May 11, 2024 GMT (1 quake)
May 11, 03:41 pm (Costa Rica)	2.9 39 km	22 km (13 mi) to the S	Costa Rica: 3 km al Sureste de Tacares, Grecia.	Info
Wednesday, May 8, 2024 GMT (1 quake)
May 7, 11:36 pm (Costa Rica)	2.6 89 km	4.2 km (2.6 mi) to the NE	Costa Rica: 6 km al Noroeste de Varablanca, Heredia.	Info

View recent quakes

Background

The broad, well-vegetated edifice of Poás has three craters in a N-S line. The 2708-m-high basaltic-to-dacitic complex stratovolcano is cut by a N-S-trending fissure that extends to the lower northern flank, where a parasite volcano (the Congo stratovolcano) and several explosion craters, or maars, most of them lake-filled, have been created.
Poás has two summit crater lakes. The southermost one, Botos, is cold, clear has not eruptied for about 7500 years. The other crater lake is geothermally heated and -after Kawah Ijen in Indonesia - is probably the world's second most acidic natural lake. Its pH is near zero.
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Source: GVP, Smithsonian Institution