Abstract Forearc basins are areas underexplored by academic or industrial research. They are not considered as potential areas by the industry because only three giant oil fields have been formed in this type of basin. One of them is located in the northern Peruvian forearc system: the Talara Basin (1.7 billion bbl to date). The aim of this work is to provide insights for the oil industry about the tectonic style and the tectonic-sedimentation relationships within this basin to decipher its petroleum potential, using surface and subsurface data (seismic lines, well-logs). From a tectonic point of view, we demonstrate that the basin is not a pull-apart basin, but an accretionary prism built by deep-seated north-verging thrusts reworked by shallow gravitational normal faults. A tectonic model is developed, which involves the northwestward propagation of thrust culminations accompanied by the development of southeast- facing normal faults since Eocene times. This tectonic model renews our perception about the entire Peruvian forearc and suggests that anticline traps, which have never been explored, should become a new target for a future hydrocarbon exploration.

ABSTRACT In the Peruvian sub-Andean foreland basin system, the construction of serial balanced cross-sections from a good set of structural data and an extensive knowledge of the stratigraphy and geodynamic evolution allow a more refined definition of the unexplored plays, as subthrusts, duplexes, or pre-Andean structures. Sequential restorations are proposed by coupling thermochronologic analyses with growth strata studies. The results show significant north–south variations in geometry, timing and rates of deformation, and foreland sedimentation. These latitudinal variations are not only related to the pre-Andean basins’ inheritance but also to the interactions between thrusts propagation, erosion, and sedimentation. Thermochronologic ages correspond to the most recent thrust-related uplifts and are supplemented by the study of stratigraphic foreland basin records that can bring to light oldest tectonic events. North of the Peruvian sub-Andean zone, thrusts propagation is controlled by thick-skinned and thin-skinned salt tectonics. Northern thick-skinned tectonics has westward vergence and is inherited from a Middle Permian fold-and-thrust belt. To the south, thrusts deformation is largely controlled by the geometry of the preserved Paleozoic sedimentary wedge and becomes progressively thin skinned. Total sub-Andean shortening varies between 70 km (43 mi) in the north and 47 km (29 mi) in the south. Sub-Andean deformation started in the Late Cretaceous. After a period of quiescence during the middle Eocene, it reactivated and is still active. Three stages of sub-Andean deformation are clearly identified and help to define the preservation time in the suggested petroleum plays.