Cordillera Darwin Metamorphic Complex

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Cordillera Darwin Metamorphic Complex
Stratigraphic range: Cretaceous
Type Complex
Underlies Tobífera Formation
Lithology
PrimaryMetasediments, metavolcanics, orthogneiss
Location
Coordinates 54°45′S69°30′W / 54.75°S 69.5°W / -54.75; -69.5 Coordinates: 54°45′S69°30′W / 54.75°S 69.5°W / -54.75; -69.5
Region Magallanes Region, Tierra del Fuego Province (Argentina)
CountryFlag of Chile.svg  Chile
Flag of Argentina.svg  Argentina
Type section
Named for Cordillera Darwin
Relief Map of Chile.jpg
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Cordillera Darwin Metamorphic Complex (Chile)

The Cordillera Darwin Metamorphic Complex is a geologic complex composed chiefly of metamorphic rocks located in southern Tierra del Fuego. It has been suggested that the Cordillera Darwin Metamorphic Complex is analogous to the Eastern Andes Metamorphic Complex. [1] [2] The Cordillera Darwin Metamorphic Complex is the only metamorphic complex in the southern Andes known to have amphibolite facies rocks containing kyanite and sillimanite which evidences high-grade metamorphism. High-grade metamorphism took place during the Cretaceous purportedly in association with the closure of the Rocas Verdes Basin. [2]

The protoliths of Cordillera Darwin Metamorphic Complex are unrelated to Tierra del Fuego Igneous and Metamorphic Complex despite present-day proximity. [2]

Related Research Articles

Darwin most often refers to:

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Mount Darwin (Andes)

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Cordillera Darwin

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Famatinian orogeny

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Tobífera Formation

Tobífera Formation is a volcano-sedimentary formation of Middle to Late Jurassic age. The formation is crops out in the Magallanes Region in southern Patagonia and Tierra del Fuego of Chile, the Santa Cruz Province of southern Argentina, and in the subsurface of the Malvinas Basin offshore Argentina and the Falkland Islands.

Tierra del Fuego Igneous and Metamorphic Complex

Tierra del Fuego Igneous and Metamorphic Complex is a geological basement complex known from boreholes in northern Tierra del Fuego. The complex is made up of foliated igneous rocks of Cambrian age including orthogneiss. It underlies unconformably the Jurassic Tobífera Formation. The protoliths of Cordillera Darwin Metamorphic Complex are unrelated to Tierra del Fuego Igneous and Metamorphic Complex despite present-day proximity.

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Geology of Peru

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References

  1. 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.
  2. 1 2 3 Hervé, F.; Fanning, C.M.; Pankhurst, R.J.; Mpodozis, C.; Klepeis, K.; Calderón, M.; Thomson, S.N. (2010). "Detrital zircon SHRIMP U–Pb age study of the Cordillera Darwin Metamorphic Complex of Tierra del Fuego: sedimentary sources and implications for the evolution of the Pacific margin of Gondwana" (PDF). Journal of the Geological Society, London. 167 (3): 555–568. doi:10.1144/0016-76492009-124.