Ultramafic rocks in the North Patagonian Andes: is their emplacement associated with the Neogene tectonics of the Liquiñe-Ofqui Fault Zone?

Serpentinites and fresh or partially serpentinized harzburgite crop out in the western slope of the North Patagonian Andes of continental Chiloé (41°44’-42°12’S). These rocks are spatially associated with low-grade metamorphic rocks containing Cenozoic detrital zircons. The metamorphic rocks, togeth...

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Detalhes bibliográficos
Autores: Hervé, Francisco, Fuentes, Francisco, Calderón, Mauricio, Fanning, Mark, Quezada, Paulo, Pankhurst, Robert, Rapela, Carlos Washington
Formato: artículo
Estado:Versión publicada
Fecha de publicación:2017
País:Argentina
Recursos:Universidad Nacional de La Plata
Repositorio:SEDICI (UNLP)
Idioma:inglés
OAI Identifier:oai:sedici.unlp.edu.ar:10915/87416
Acesso em linha:http://sedici.unlp.edu.ar/handle/10915/87416
Access Level:acceso abierto
Palavra-chave:Geología
Liquiñe-Ofqui fault zone
Neogene tectonics
North patagonian andes
Serpentinites
Serpentinitas
Andes norpatagónicos
Zona de Falla Liquiñe Ofqui
Tectónica neógena
Descrição
Resumo:Serpentinites and fresh or partially serpentinized harzburgite crop out in the western slope of the North Patagonian Andes of continental Chiloé (41°44’-42°12’S). These rocks are spatially associated with low-grade metamorphic rocks containing Cenozoic detrital zircons. The metamorphic rocks, together with Devonian metasediments, have been mapped previously as Late Paleozoic-Triassic metamorfic complex, an age no longer tenable for at least part of the complex. Transpressional tectonic emplacement of the ultramafic body or bodies is thought to have been related to activity on the Liquiñe-Ofqui Fault Zone, following a late Oligocene-Early Miocene extensional phase in the forearc region of the present Andes. This fault zone occurs immediately east of the outcrops of the ultramafic rocks and has been interpreted previously as generating a hemi-flower or flower structure.