Application of conceptual targeting approaches in porphyry copper exploration: Examples from the Cordillera de Domeyko, northern Chile

Abstract

The Cordillera de Domeyko of northern Chile has been traditionally interpreted as a major sinistral strike-slip fault system that controlled the emplacement of the Paleocene — Oligocene age giant porphyry Cu deposits of the region. New field studies combined with construction of cross-sections and re-evaluation of new and existing thermochronological data show that the Cordillera de Domeyko is dominated by N-S striking, moderate to steeply dipping inverted extensional faults, thrusts and associated folds, with no evidence of significant sinistral strike-slip faulting. The Cu bearing porphyry intrusions are controlled by these inverted extensional fault systems. A new model of inversion of pre-existing, Triassic — Cretaceous, back-arc extensional faults for the tectonic control on the emplacement of these giant porphyry Cu deposits in northern Chile is proposed, and its application to areas covered by post-mineral sedimentary deposits is presented.