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Below is a summary of eruption dates and Volcanic Explosivity Indices (VEI).

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.

Casertano L, 1963a. Chilean Continent. {Catalog of Active Volcanoes of the World and Solfatara Fields}, Rome: IAVCEI, 15: 1-55

de Silva S L, Francis P W, 1991. {Volcanoes of the Central Andes}. Berlin: Springer-Verlag, 216 p

Francis P W, Roobol M J, Walker G P L, Cobbold P R, Coward M, 1974. The San Pedro and San Pablo volcanoes of northern Chile and their hot avalanche deposits. {Geol Rundschau}, 63: 357-388

Gonzalez-Ferran O, 1995. {Volcanes de Chile}. Santiago: Instituto Geografico Militar, 635 p

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

O'Callaghan L J, Francis P W, 1986. Volcanological and petrological evolution of San Pedro volcano, Provincia El Loa, north Chile. {J Geol Soc London}, 143: 275-286

Worner G, Hammerschmidt K, Henjes-Kunst F, Lezaun J, Wilke H, 2000. Geochronology (40Ar/39Ar, K-Ar and He-exposure ages) of Cenozoic magmatic rocks from Northern Chile (18-22° S): implications for magmatism and tectonic evolution of the central Andes. {Rev Geol Chile}, 27: 205-240

The composite volcano of San Pedro in the arid Atacama desert of northern Chile is one of the world's highest historically active volcanoes. The 6145-m-high basaltic andesite-to-dacitic San Pedro is located to the west of its older twin volcano, 6092-m-high San Pablo. The youngest cone of San Pedro was constructed within a large horseshoe-shaped escarpment left by the collapse of an older edifice, which produced a large debris avalanche to the west, perhaps accompanied by a major pumice eruption. Thick dacitic lava flows with steep-sided fronts mantle the upper portion of the younger cone. The youthful-looking La Poruña scoria cone on the western flank produced an 8-km-long lava flow, but Worner et al. (2000) obtained a surprisingly old Helium surface-exposure age of 103,000 years from a juvenile block of the lava flow. Reports of variable reliability mention historical eruptions of San Pedro in the 19th and 20th centuries.