Abanico Formation
Abanico Formation (Spanish: Formación Abanico) is a 3 km thick sedimentary formation exposed in the Andes of Central Chile.[1] The rocks of the formation sedimented in a timespan from the Eocene to the Miocene. Abanico Formation's contact with the Miocene Farellones Formation that overlies it has been the subject of differing interpretations since the 1960s.[2]
The sediments accumulated in the Abanico Extensional Basin within a context of the Andean orogeny. The basin had an north-south elongated shape that spanned the latitudes of 29–38° S. Tectonic inversion from 21 to 16 million years ago made the basin collapse and the sediments to be incorporated to the Andean cordillera.[3] The northern part of the basin inverted before the southern part.[2] Parts of the formation are known to have experienced Prehnite-pumpellyite facies metamorphism.[1]
The Tinguiririca fauna is known from the fossils found in the Abanico Formation near Tinguiririca River.
References
- 1 2 Muñoz, Marcia; Aguirre, Luis; Vergara, Marío; Demant, Alain; Fuentes, Francisco; Fock, Andrés (2010). "Prehnite-pumpellyite facies metamorphism in the Cenozoic Abanico Formation, Andes of central Chile (33º50'S): chemical and scale controls on mineral assemblages, reaction progress and the equilibrium state" (PDF). Andean Geology 37 (1): 54–77. Retrieved 30 December 2015.
- 1 2 Godoy, Estanislao (2012). "Sobre el variable marco geotectónico de las formarciones Abanico y Farellones y sus equivalentes al ser de los 35°LS". Revista de la Asociación Geológica Argentina (in Spanish) 69 (4): 570–577. Retrieved 30 December 2015.
- ↑ Charrier, Reynaldo; Pinto, Luisa; Rodríguez, María Pía (2006). "3. Tectonostratigraphic evolution of the Andean Orogen in Chile". In Moreno, Teresa; Gibbons, Wes. Geology of Chile. Geological Society of London. pp. 93–94. ISBN 9781862392199.