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Quantifying interactions between uplift, climate, deformation and exhumation processes remains difficult, mainly due to a paucity of data relevant to all processes. Central Andes are a prime example to study the respective role of climate forcing and tectonic activity on mountain building. In this study we propose new data (thermochronology, biostratigraphy, field observations and seismic interpretations) focused on the Eastern Cordillera (EC) and the Sub-Andean Zone (SAZ) of southern Peru between 12oS and 14oS, in order to i) constrain the timing of deformation, and to ii) demonstrate that contrary to recent studies, our new data outline that the Plio-Peistocene uplift and erosion of the Andes are more likely related to thrust induced exhumation than to a climate forcing. Low temperature thermochronological results obtained for the EC and the SAZ, as well as the growth strata documented in seismic and on the field allow to determine two main deformation periods: i) from the Oligocene to Middle Miocene (~25-14 Ma), and ii) from the Late Miocene to Pleistocene (~10-2.8 Ma). The Plio-Pleiostocene cooling induced by the erosion of the EC in southern Peru is not controlled by climatic change, but better by the development of duplex in the Andean front.

In the Peruvian Subandean fold and thrust belt, the construction of 4 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 sub-thrusts, duplexes or pre-Cretaceous structures. Sequential restorations are proposed by coupling thermochronologic analyses with growth strata studies. The results show significant north-south variations in the geometry, the timing and the rate of the deformation. This latitudinal variation is related to the pre-Andean basins inheritance, but also to the Andean slab geometry. Thermochronologic ages correspond to the most recent tectonic uplifts and cannot be disassociated from the study of growth strata that might have recorded oldest events. North of the Peruvian Subandean zone, the thrusts propagation seems continuous since the Late Cretaceous. In the south, two stages of Cenozoic deformation are clearly indentified.