Quaternary propagation of the western mountain front of the Barreal block, Precordillera of Argentina (31º30`-32º00`S)

TERRIZZANO, C. M.; YAMIN, M, G.; CORTÉS, J. M., GARCÍA MORABITO, E.

Antofagasta

Congreso; XIII Congreso Geológico Chileno; 2012

Universidad Católica del Norte

Abstract. The N-S-trending Barreal block on the western edge of the Precordillera Sur of Argentina shows topographic, structural and geomorphologic along-strike variations. Differences in the degree of exhumation are the result of how Neogene and Quaternary deformation progressed along this mountainous front, propagating from its central portion to its northern and southern borders. To the north the oldest Quaternary alluvial deposits are faulted showing a migration of the deformation to the hinterland. Furthermore, youngest Quaternary deformation is concentrated at the southern edge, from where it propagates southwards into the piedmont area and links to an oblique sinistral deformation zone. This deformation is interpreted as controlled by pre Cenozoic mechanical anisotropies of the basement. Thus, anisotropies seem to play a key role in the location, progression and kinematics of the Late-Cenozoic deformation of the area.