The Mesozoic to Cenozoic deformation of the Andean forearc of northern Chile is interpreted as a mix of crustal extension, contraction and strike-slip faulting. The effects of these diverse processes on the evolution of the western slope of the Central Andes have been widely debated. However, some factors (e.g. the initial distribution of the Pre-Andean structural and stratigraphic elements, the location and nature of the main sediment sources active during the deformation, the timing of Andean uplift and the location of synorogenic depocenters) are still unknown. In response to these questions and to update our previous knowledge of the tectonic evolution of the Andean forearc, we developed a regional study of the Calama Basin and surrounding areas considering the occurrence of good exposures and the availability of subsurface data. We integrated previous and new field data, 2D seismic profiles and zircon U–Pb ages from Mesozoic to Cenozoic units. Our results indicate a Triassic–Jurassic deformation dominated by rifting that progressed from an intracontinental domain, with the development of isolated half-graben in the Triassic, to the opening of broad marine rift-related basins during Jurassic times, thus confirming many of the interpretations made previously for the Pre-Andean evolution of northern Chile. The new ages of the continental post-rift units suggest that the rift system remained active at 95 Ma. After the post-rift units, the Late Cretaceous orogenic history started with the inversion of pre-existing Triassic and Jurassic rift-related structures, thus allowing the extrusion of synrift and post-rift strata. The latter is well outlined by the Chintoraste Fault exposed in the Loa and San Salvador rivers. During this period, the Andean deformation front was positioned in this region, as recorded by nearly 2 km of Upper Cretaceous to Paleocene synorogenic strata deposited on the inversion anticlines. From the Eocene, an important basement-involved tectonism took place as a result of the eastward migration of the Andean deformation front. The latter allowed the unroofing of the Paleozoic pre-rift basement blocks, creating a topographic relief dominated by contractional intermontane basins (e.g. the Calama Basin). These were filled by sediments eroded from the basement blocks (e.g. the Sierra Limón Verde and Tuina sectors) elevated by reverse faults and by the Mio-Pliocene volcanic products of the magmatic arc.

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