Tectonic evolution of the late Paleozoic basement in western Patagonia region (Argentina-Chile).

• Autores: Marcos, Paulo; González, Pablo Diego; Renda, Emiliano Manuel; Oriolo, Sebastián; Varela, María Eugenia; Gregori, Daniel Alfredo
• Año de publicación: 2021
• Idioma: inglés
• Tipo de recurso: documento de conferencia
• Materia: Ciencias de la Tierra (General); Metamorphism; Tectonics; Patagonia; Comallo; Geodynamics; Ciencias de la Tierra (General)
• Institución: Universidad Nacional de Río Negro

Fil: Marcos, Paulo. Universidad Nacional de Río Negro. Instituto de Investigación en Paleobiología y Geología. Río Negro, Argentina.
Fil: González, Pablo Diego. Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Argentina. Servicio Geológico Minero Argentino, Centro General Roca, Río Negro, SEGEMAR Regional Sur, Independencia 1495, Parque Industrial 1, Gral. Roca, (Río Negro), C. P. 8332, Casilla, Correo, Argentina.
Fil: Renda, Emiliano Manuel. Universidad Nacional de Río Negro. Instituto de Investigación en Paleobiología y Geología. Río Negro, Argentina.
Fil: Oriolo Sebastián. CONICET-Universidad de Buenos Aires. Instituto de Geociencias Básicas, Aplicadas y Ambientales de Buenos Aires (IGEBA), Intendente Güiraldes 2160, C1428EHA, Buenos Aires, Argentina.
Fil: Varela, María Eugenia. ICATE-CONICET, Av. España 1512 sur, 5400, San Juan, Argentina.
Fil: Gregori, Daniel Alfredo. Departamento de Geología, Universidad Nacional del Sur and INGEOSUR, San Juan 670, 8000 Bahía Blanca, Argentina.
Marcos, P., González, P.D., Renda, E., Oriolo, S., Suárez, R., Varela, M., Gregori, D. 2021. Tectonic evolution of the late Paleozoic basement in western Patagonia region (Argentina-Chile). Metamorphic Studies Group Research in Progress Meeting. The Mineralogical Society. Abstract Volume, p. 56. Virtual meeting 29-31 March 2021.
Patagonia constitutes a vast area located in the southern extreme of the South American Continent, where the igneous-metamorphic basement presents a complex evolution during the Paleozoic. The oldest outcrops are in the northeastern region near the Atlantic Ocean and correspond to the Cambrian - Ordovician Orogens [1,2]. In contrast, its western region comprises basement units of Silurian – Devonian ages, showing that orogen-development processes migrated towards the southwest of Patagonia [3,4,5]. The last widespread igneous-metamorphic events record the Late Paleozoic Gondwanide Orogeny and are extensively distributed along the Patagonia's boundaries [2,6,7,8]. However, in the western boundary of the Patagonian region, only a few P-T-t path reconstructions were made for the late Paleozoic metamorphic basement [6,7,9,10]. These evolutionary P-T-t models were linked with the subduction of the Proto-Pacific Ocean plate along an active continental margin in southwestern Gondwana. The present contribution aims to review the different geodynamic conditions of the western Patagonia region and establish their relationship with the paleotectonic evolution during the late Paleozoic times. The late Carboniferous metamorphic complexes exposed at the Andean Cordillera in western Patagonia achieve blueschists-amphibolite facies conditions developing HP-LT progressive metamorphic paths [7,9,10]. The uplift beginning of these accretionary prism-arc basements was coeval with the arc migration throw inboard the continent during early Permian times [6,7]. In this extra-Andean region, stromatic migmatites attained MP-HT conditions at the beginning of the Permian magmatic arc development [6,11]. Finally, the magmatism migration continued far inside the continent during the rest of the Permian period [2,11]. Further P-T-t estimations of these basement regions will improve the knowledge of the late Paleozoic evolution in the Patagonia region and its relationship with the paleotectonic subduction process. References: [1] González et al. (2019) Gondwana Research 63:186-225 [2] Pankhurst et al. (2006) Earth-Sci Rev 76:235-257 [3] Marcos et al. (2018) Geoscience Frontiers 9 (2), 485–504. [4] Renda et al. (2020) Journal of South American Earth Sciences 106:103045 [5] Suarez et al. (2019) Journal of South American Earth Sciences 95.102256. [6] Marcos et al. (2020) Lithos 376-377:105801 [7] Oriolo et al. (2019) Tectonics 38 (7), 2378–2400. [8] Castillo et al. (2017) Journal of the Geological Society 174 (5), 803–816. [9] Willner et al. (2004) Lithos 75 (3–4), 283–310. [10] Willner et al. (2005) Journal of Petrology 46 (9), 1835–1858. [11] Gregori et al. (2020) International Geology Review 1-25.