San Pedro

Photo of this volcano
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  • Country
  • Volcanic Region
  • Primary Volcano Type
  • Last Known Eruption
  • 21.88°S
  • 68.4°W

  • 6145 m
    20156 ft

  • 355070
  • Latitude
  • Longitude

  • Summit
    Elevation

  • Volcano
    Number

The Global Volcanism Program has no activity reports for San Pedro.

The Global Volcanism Program has no Weekly Reports available for San Pedro.

The Global Volcanism Program has no Bulletin Reports available for San Pedro.

Basic Data

Volcano Number

Last Known Eruption

Elevation

Latitude
Longitude
355070

1960 CE

6145 m / 20156 ft

21.88°S
68.4°W

Volcano Types

Stratovolcano(es)
Lava dome(s)
Pyroclastic cone

Rock Types

Major
Andesite / Basaltic Andesite
Dacite

Tectonic Setting

Subduction zone
Continental crust (> 25 km)

Population

Within 5 km
Within 10 km
Within 30 km
Within 100 km
0
156
2,349
150,795

Geological Summary

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 edifice is W 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 W 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.

References

The following references have all been used during the compilation of data for this volcano, it is not a comprehensive bibliography.

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.

Eruptive History


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


Start Date Stop Date Eruption Certainty VEI Evidence Activity Area or Unit
1960 Dec 2 Unknown Confirmed 2 Historical Observations
1938 Feb Unknown Confirmed 2 Historical Observations
[ 1923 ] [ Unknown ] Uncertain    
[ 1917 ] [ Unknown ] Uncertain    
[ 1916 ] [ Unknown ] Uncertain    
1911 Sep Unknown Confirmed 2 Historical Observations
1901 May 25 1901 Aug Confirmed 2 Historical Observations
1891 (?) Unknown Confirmed 2 Historical Observations
1877 (?) Unknown Confirmed 2 Historical Observations
[ 1870 ] [ Unknown ] Uncertain    

This compilation of synonyms and subsidiary features may not be comprehensive. Features are organized into four major categories: Cones, Craters, Domes, and Thermal Features. Synonyms of features appear indented below the primary name. In some cases additional feature type, elevation, or location details are provided.


Cones

Feature Name Feature Type Elevation Latitude Longitude
Poruña, La Cone 3545 m 21° 53' 0" S 68° 30' 0" W
San Pablo Twin volcano 5334 m 21° 53' 0" S 68° 20' 0" W

Photo Gallery


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 San Pedro (left) is located to the west of its older twin volcano, 6092-m-high San Pablo (center). The youngest cone of San Pedro was constructed within the horseshoe-shaped crater left by the collapse of an older edifice, which produced a large debris avalanche to the west. Reports of variable reliability mention historical eruptions in the 19th and 20th centuries.

Photo by Oscar González-Ferrán (University of Chile).

Smithsonian Sample Collections Database


A listing of samples from the Smithsonian collections will be available soon.

Affiliated Sites

Large Eruptions of San Pedro Information about large Quaternary eruptions (VEI >= 4) is cataloged in the Large Magnitude Explosive Volcanic Eruptions (LaMEVE) database of the Volcano Global Risk Identification and Analysis Project (VOGRIPA).
WOVOdat WOVOdat is a database of volcanic unrest; instrumentally and visually recorded changes in seismicity, ground deformation, gas emission, and other parameters from their normal baselines. It is sponsored by the World Organization of Volcano Observatories (WOVO) and presently hosted at the Earth Observatory of Singapore.
EarthChem EarthChem develops and maintains databases, software, and services that support the preservation, discovery, access and analysis of geochemical data, and facilitate their integration with the broad array of other available earth science parameters. EarthChem is operated by a joint team of disciplinary scientists, data scientists, data managers and information technology developers who are part of the NSF-funded data facility Integrated Earth Data Applications (IEDA). IEDA is a collaborative effort of EarthChem and the Marine Geoscience Data System (MGDS).
MODVOLC - HIGP MODIS Thermal Alert System Using infrared satellite Moderate Resolution Imaging Spectroradiometer (MODIS) data, scientists at the Hawai'i Institute of Geophysics and Planetology, University of Hawai'i, developed an automated system called MODVOLC to map thermal hot-spots in near real time. For each MODIS image, the algorithm automatically scans each 1 km pixel within it to check for high-temperature hot-spots. When one is found the date, time, location, and intensity are recorded. MODIS looks at every square km of the Earth every 48 hours, once during the day and once during the night, and the presence of two MODIS sensors in space allows at least four hot-spot observations every two days. Each day updated global maps are compiled to display the locations of all hot spots detected in the previous 24 hours. There is a drop-down list with volcano names which allow users to 'zoom-in' and examine the distribution of hot-spots at a variety of spatial scales.
MIROVA Middle InfraRed Observation of Volcanic Activity (MIROVA) is a near real time volcanic hot-spot detection system based on the analysis of MODIS (Moderate Resolution Imaging Spectroradiometer) data. In particular, MIROVA uses the Middle InfraRed Radiation (MIR), measured over target volcanoes, in order to detect, locate and measure the heat radiation sourced from volcanic activity.