Divisadero Group

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Divisadero Group
Stratigraphic range: AptianAlbian
Type Geologic group
Underlies Cerro Plataforma, La Cascada, Ligorio Márques & Cardiel Formations
Overlies Coihaique Group
Lithology
Primary Pyroclastic rock, lava
Location
Location Patagonia
Coordinates 45°30′S72°00′W / 45.500°S 72.000°W / -45.500; -72.000
Region Chubut Province
Aysén Region
CountryArgentina
Chile
Extent Magallanes or Austral Basin
Type section
Named byHeim
Year defined1940
Relief Map of Argentina.jpg
Green pog.svg
Divisadero Group (Argentina)

The Divisadero Group is a group of geological formations in the Magallanes Basin (Chile) or Austral Basin (Argentina) of northwestern Patagonia. It overlies the Coihaique Group. [1] The group is chiefly made up of pyroclastic rocks and lavas of the calc-alkaline magma series. [1] Rocks are of andesite and rhyolite composition. [2]

Contents

Geographic extent

In Chile, the formation crops out in Aysén Region [1] while in Argentina it can be found in Chubut Province. [2]

Tectonic movements during the Miocene have significantly deformed Divisadero Group. [3]

See also

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References

  1. 1 2 3 Suárez, Manuel; de la Cruz, Rita (1994). Estratigrafía y paleogeografía mesozoica de Aisén nororiental (45-46 lat.s.), Chile (PDF). 7° Congreso Geológico Chileno (in Spanish). Concepción: Universidad de Concepción. pp. 538–542. Archived from the original (PDF) on December 28, 2017.
  2. 1 2 Haller, Miguel J.; Lapido, Omar R. (1980). "El Mesozoico de la Cordillera Patagónica Central". Revista de la Asociación Geológica Argentina (in Spanish). XXXV (2): 230–247. Retrieved January 4, 2018.
  3. Aptian-Albian subaerial volcanic rocks in central Patagonia: Divisadero and Chubut Groups