Irazú

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  • Country
  • Subregion Name
  • Primary Volcano Type
  • Last Known Eruption
  • 9.979°N
  • 83.852°W

  • 3432 m
    11257 ft

  • 345060
  • Latitude
  • Longitude

  • Summit
    Elevation

  • Volcano
    Number

There are no activity reports for Irazú.



 Available Weekly Reports

There are no Weekly Reports available for Irazú.

Summary of eruption dates and Volcanic Explosivity Indices (VEI).

Start Date Stop Date Eruption Certainty VEI Evidence Activity Area or Unit
1994 Dec 8 1994 Dec 8 Confirmed 2 Historical Observations Upper NW flank
1977 Mar 3 Unknown Confirmed 1 Historical Observations
[ 1974 Mar 2 ] [ 1974 Mar 7 ] Discredited    
[ 1967 Aug 7 ] [ Unknown ] Discredited    
1963 Mar 13 1965 Feb 13 Confirmed 3 Historical Observations
[ 1962 Aug 9 ] [ Unknown ] Discredited    
1939 May 18 1940 Feb Confirmed 2 Historical Observations
1933 Mar 22 (?) 1933 Jul 25 Confirmed 2 Historical Observations
1930 Oct Unknown Confirmed 2 Historical Observations
1928 Feb 14 1928 May 26 ± 5 days Confirmed 2 Historical Observations
1924 Mar 1924 Apr Confirmed 2 Historical Observations
1917 Sep 27 1921 Confirmed 3 Historical Observations
[ 1914 Feb 21 ] [ Unknown ] Uncertain    
[ 1910 ] [ Unknown ] Discredited    
[ 1909 ] [ Unknown ] Uncertain 2  
[ 1899 ] [ Unknown ] Discredited    
[ 1894 ] [ Unknown ] Discredited    
[ 1889 Feb 28 ] [ Unknown ] Discredited    
1886 Unknown Confirmed 2 Historical Observations
1885 Unknown Confirmed 2 Historical Observations
[ 1883 Jan 3 ] [ Unknown ] Discredited    
[ 1882 ] [ Unknown ] Uncertain 2  
1875 ± 5 years Unknown Confirmed 2 Historical Observations
1864 Sep 16 1864 Sep 17 Confirmed 2 Historical Observations
1847 May 18 Unknown Confirmed 2 Historical Observations
[ 1844 May ] [ Unknown ] Uncertain 2  
1842 Unknown Confirmed 2 Historical Observations
[ 1826 ] [ Unknown ] Uncertain    
1823 Unknown Confirmed 2 Historical Observations
1822 May 7 Unknown Confirmed 2 Historical Observations
[ 1821 May ] [ Unknown ] Uncertain 2  
1775 (?) Unknown Confirmed 2 Historical Observations
1726 May Unknown Confirmed 2 Historical Observations Diego de la Haya Crater
1723 Feb 16 1724 Feb (?) Confirmed 3 Historical Observations Diego de la Haya Crater
1560 ± 75 years Unknown Confirmed 3 Radiocarbon (corrected)
1110 ± 100 years Unknown Confirmed 3 Radiocarbon (corrected)
0690 ± 40 years Unknown Confirmed 3 Radiocarbon (corrected)
0430 ± 500 years Unknown Confirmed 3 Radiocarbon (corrected)
0640 BCE ± 500 years Unknown Confirmed 3 Radiocarbon (corrected)

The following references are the sources used for data regarding this volcano. References are linked directly to our volcano data file. Discussion of another volcano or eruption (sometimes far from the one that is the subject of the manuscript) may produce a citation that is not at all apparent from the title. Additional discussion of data sources can be found under Volcano Data Criteria.

Alvarado G E, 1989. Los Volcanes de Costa Rica. San Jose, Costa Rica: Universidad Estatal a Distancia, 175 p.

Alvarado G E, 2000. Volcanes de Costa Rica: su geologia, historia y riqueza natural. San Jose, Costa Rica: EUNED, 269 p.

Alvarado G E, 1993. Volcanology and petrology of Irazu volcano, Costa Rica. Unpublished PhD thesis, Christian-Albrechts Univ, 261 p.

Alvarado G E, Carr M J, Turrin B D, Swisher CC III, Schmincke H-U, Hudnut K W, 2006. Recent volcanic history of Irazu volcano, Costa Rica: alternation and mixing of two magma batches, and pervasive mixing. In: Rose W I, Bluth G J S, Carr M J, Ewert J W, Patino L C, Vallance J W (eds), Volcanic hazards in Central America, {Geol Soc Amer Spec Pap}, 412: 259-276.

Alvarado G E, Vega E, Chaves J, Vasquez M, 2004. Los grandes deslizamientos (volcanicos y no volcanicos) de tip debris avalanche en Costa Rica. Rev Geol Amer Central, 30: 83-99.

Alvarado-Induni G E, 2005. Costa Rica, Land of Volcanoes. San Jose, Costa Rica: EUNID, 306 p.

Barquero-H J, 1998b. Volcan Irazu. San Jose, Costa Rica: privately published, 50 p.

Barquero-H J, Saenz-R R, 1987. Aparatos volcanicos de Costa Rica. Heredia, Costa Rica: OVSICORI-UNA, 1:750,000 map and volcano list.

Carr M J, 1984. Symmetrical and segmented variation of physical and geochemical characterisitics of the Central American volcanic front. J Volc Geotherm Res, 20: 231-252.

Hidalgo P J, Alvarado G E, Linkimer L, 2004. La Lavina del Valle Central (Costa Rica): lahar o debris avalanche?. Rev Geol Amer Central, 30: 101-109.

IAVCEI, 1973-80. Post-Miocene Volcanoes of the World. IAVCEI Data Sheets, Rome: Internatl Assoc Volc Chemistry Earth's Interior..

Krushensky R D, Escalante G, 1967. Activity of Irazu and Poas volcanoes, Costa Rica, November 1964-July 1965. Bull Volc, 31: 75-84.

Mooser F, Meyer-Abich H, McBirney A R, 1958. Central America. Catalog of Active Volcanoes of the World and Solfatara Fields, Rome: IAVCEI, 6: 1-146.

Murata K J, Dondoli C, Saenz R, 1966. The 1963-65 eruption of Irazu volcano, Costa Rica. Bull Volc, 29: 765-793.

Sapper K, 1925. The Volcanoes of Central America. Halle: Verlag Max Niemeyer, 144 p.

Scott K C, Reagan M K, Trimble D A, 2006. Tephra deposits for the past 2600 years from Irazu volcano, Costa Rica. In: Rose W I, Bluth G J S, Carr M J, Ewert J W, Patino L C, Vallance J W (eds), Volcanic hazards in Central America, {Geol Soc Amer Spec Pap}, 412: 225-234.

Siebert L, Alvarado G E, Vallance J W, van Wyk de Vries B, 2006. Large-volume volcanic edifice failures in Central America and associated hazards. In: Rose W I, Bluth G J S, Carr M J, Ewert J W, Patino L C, Vallance J W (eds), Volcanic hazards in Central America, {Geol Soc Amer Spec Pap}, 412: 1-26.

Stine C M, Banks N G, 1991. Costa Rica volcano profile. U S Geol Surv Open-File Rpt, 67 p.

Irazú, Costa Rica's highest volcano and one of its most active, rises to 3432 m immediately east of the capital city of San José. The massive volcano covers an area of 500 sq km and is vegetated to within a few hundred meters of its broad flat-topped summit crater complex. At least 10 satellitic cones are located on the southern flank of Irazú. No lava flows have been identified from Irazú since the eruption of the massive Cervantes lava flows from south-flank vents about 14,000 years ago, and all known Holocene eruptions have been explosive. The focus of eruptions at the summit crater complex has migrated to the west towards the historically active crater, which contains a small lake of variable size and color. Although eruptions may have occurred around the time of the Spanish conquest, the first well-documented historical eruption occurred in 1723, and frequent explosive eruptions have occurred since. Ashfall from the last major eruption of Irazú during 1963-65 caused significant disruption to San José and surrounding areas.