EVOLUCION GEODINAMICA DEL OLIGO-MIOCENO EN LOS ANDES PRINCIPALES (31°30′S), PROVINCIA DE SAN JUAN Y MENDOZA, ARGENTINA

PÉREZ DANIEL J.

San Miguel de Tucuman

Congreso; XX° Congreso Geológico Argentino, Tucuman, Argentina; 2017

Asociación Geológica Argentina (AGA)

The present contribution analyzes the stratigraphic and structural characteristics of the deposits of volcanic rocks of Miocene Oligocene age and its relation with Paleozoic, Mesozoic and Cenozoic deposits in the Principal Andes. New radimetric ages of these deposits of volcanic rocks, allow the differentiation of two large groups of volcanic rocks, which indicate for this region the existence of a new phase of deformation, of early Miocene age, corresponding to the Pehuenche event. This phase of deformation would have acted approximately between 21 and 18 Ma, presents regional characteristics and would have been responsible for deforming the volcaniclastic deposits of the Abanico basin, represented by the Los Pelambres and Pachón Formations, from the town of Altar (31º30 ´ S) to the town of Las Cuevas (32º50 ´S).The study region is located along the border between Argentina and Chile, west of the Santa Cruz mountain range, La Ramada, Espinacito, Aconcagua hill, in the province of San Juan and Mendoza 31º30´S-70 ° 15´W, and covers the geological provinces of the Frontal and Principal Cordillera.