Structural section of the Trancas-Choromoro valley, Tucumán Province (Argentina

Abstract

Structural section of the Trancas-Choromoro valley, Tucumán Province (Argentina)?. The structure of the Trancas-Choromoro valley is described on the basis of a balanced cross section between Cumbres Calchaquíes and the Sierra de Medina. It is typified by an westward dipping thrust belt produced by tectonic inversion of the southern part of the Cretaceous Salta Group rift due to compressive stress related to the Andean tectonics. The main deformation mechanism has been fault-bend folding, that shortened the section 19%. The thrusts develop a leading and a trailing imbricate fan, westwards and eastwards of the valley axis, respectively. This depression express an area of minor net slip in the thrust belt. The correlation of the Choromoro Group with the Sub-Andean Tertiary, as well as with the Miocenic ingression is presented.