Coastal Batholith of central Chile

Summary

The Coastal Batholith of central Chile is a group of plutons in the Chilean Coast Range of Central Chile appearing contiguously from 33° S to 38° S.[1][2] At a latitude of 40° S an outlying group of plutons of the batholith appear in a more eastward position in the Andes.[1]

Coastal Batholith of central Chile
Stratigraphic range: Pennsylvanian
322.0–297.6 Ma
Araucarias growing on top of rocks of the Coastal Batholith, Cordillera de Nahuelbuta
TypeBatholith
Unit ofCentral Chile, Andes
Lithology
PrimaryCalc-alkaline magma series
Location
LocationChilean Coast Range
Coordinates37°30′S 73°00′W / 37.500°S 73.000°W / -37.500; -73.000
RegionAraucanía, Biobío, Los Ríos, Maule, O'Higgins, Santiago Metropolitan & Valparaíso Regions
Country Chile

Geological sketch map of central Chile 33° and 40°S with the Coastal Batholith and rocks of the accretionary metamorphic prism - age data are U-Pb zircon crystallization ages

Together with the Elqui-Limarí Batholith and the Colangüil Batholith, the Coastal Batholith of central Chile is a remnant of the volcanic arcs that erupted the volcanic material of the Choiyoi Group. During the Permian the zone of arc magmatism moved from the Coastal Batholith 350 km inland reaching San Rafael about 280 million years ago.[2] The batholith is emplaced amidst metamorphic rocks belonging to a Paleozoic accretionary complex. The northern parts are of the batholith are themselves intruded by Jurassic gabbros.[1]

Rocks of the batholith belong to the calc-alkaline magma series.[3]

References edit

  1. ^ a b c Deckart, Katja; Hervé, Francisco; Fanning, C. Mark; Ramírez, Valeria; Calderón, Mauricio; Godoy, Estanislao (2014). "U-Pb Geochronology and Hf-O Isotopes of zircons from the Pennsylvanian Coastal Batholith, South-Central Chile". Andean Geology. 41 (1). doi:10.5027/andgeoV41n1-a03. Retrieved 5 January 2016.
  2. ^ a b Kleiman, Laura E.; Japas, María S. (2009). "The Choiyoi volcanic province at 34°S–36°S (San Rafael, Mendoza, Argentina): Implications for the Late Palaeozoic evolution of the southwestern margin of Gondwana". Tectonophysics. 473 (3–4): 283–299. Bibcode:2009Tectp.473..283K. doi:10.1016/j.tecto.2009.02.046. hdl:11336/75328. Retrieved 5 January 2016.
  3. ^ Hervé, F.; Faundez, V.; Calderón, M.; Massonne, H.-J.; Willner, A.P. (2007). "Metamorphic and plutonic basement complexes". In Moreno, Teresa; Gibbons, Wes (eds.). The Geology of Chile. Geological Society of London. pp. 7–20.