Paleozoic Gondwanan structure along the Maule river valley between Toconey and Constitución (35.4°S, Chilean Pacific Coast)

• DOI: 10.1016/j.jsames.2023.104246
• Publication Date: 2023-02-06T17:43:50Z
• Authors: Joaquín García-Sa...; Pedro Farias; Gloria Gallastegui; Nemesio Heredia; Andrés Cuesta; Alvaro Rubio-Ordóñez; Fidel Martín-Gonz...; Jennifer Santos-M...; Camilo Palape; Olga García-Moreno
• Keywords: Orogeny; Basement; Batholith

During the late Carboniferous–middle Permian, basement of Chilean Coastal Cordillera was deformed by Gondwanan Orogeny, developed subduction Paleo-Pacific plate under Gondwana from early Carboniferous. In Maule sector (35.4°S), following metamorphic rock units are distinguished: (i) Western Series, formed metapelites, metabasites, metacherts, metaconglomerates, and marbles, mixed in a channel, with probably ages between Cambrian Carboniferous; (ii) Eastern consisting metasediments fore-arc basin, Carboniferous age. Series two recognized terms lithology deformation style: Pelitic Sandy Series. Three episodes have been distinguished, affecting both series unequaly. D1 structures consist foliation (S1) high-pressure low-temperature conditions, while it comprise tight east-verging folds, associated S1 low PT conditions (greenschist facies). D2 only present represent exhumation accretionary prism its emplacement to east over development recumbent folds thick shear-zone. Difficulties propagation presence Batholith led D3 event, well represented Los Tablones Back-thrust as N–S open right conditions.