The inversion of Mesozoic extensional structures in the Northern Andes has controlled the location of syn-orogenic successions and the dispersal of detritus since latest Maastrichtian time. Our results are supported by detailed geological mapping, integrated provenance (petrography, heavy minerals, geochronology) analysis and chronostratigraphical correlation (palynological and geochronology data) of 13 areas with Palaeogene strata across the central segment of the Eastern Cordillera. Spatial and temporal variation of sedimentation rates and provenance data indicate that mechanisms driving the location of marginal and intraplate uplifts and tectonic subsidence vary among syn-orogenic depocentres. In the late Maastrichtian–mid-Palaeocene time, crustal tilting of the Central Cordillera favoured reverse reactivation of the western border of the former extensional Cretaceous basin. The hanging wall of the reactivated fault separated two depocentres: a western depocentre (in the Magdalena Valley) and an eastern depocentre (presently along the axial zone of the Eastern Cordillera, Llanos foothills and Llanos Basin). In late Palaeocene–early Eocene time, as eastern subduction of the Caribbean Plate and intraplate magmatics advanced eastwards, reactivation of older structures migrated eastwards up to the Llanos Basin and disrupted the eastern depocentre. In early Eocene time, these three depocentres were separated by two low-amplitude uplifts that exposed dominantly Cretaceous sedimentary cover. Syn-orogenic detrital sediments supplied from the eastwards-tilted Central Cordillera reached areas of the axial domain of the Eastern Cordillera, whereas unstable metamorphic and sedimentary fragments recorded in the easternmost depocentre were supplied by basement-cored uplifts with Cretaceous and Palaeozoic sedimentary cover reported in the southern Llanos Basin. This tectonic configuration of low-amplitude uplifts separating intraplate syn-orogenic depocentres and intraplate magmatic activity in Palaeocene time was primary controlled by subduction of the Caribbean Plate.Supplementary material:Appendix 1 presents detailed descriptions of analytical methods used in this manuscript. Appendixes 2 to 4 include raw data of sandstone petrography, heavy minerals and U–Pb detrital zircon geochronology, respectively. All this material is available at http://www.geolsoc.org.uk/18597.

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We report the paleomagnetic and magnetic fabric results of 58 sites from Cretaceous-Miocene marine and continental strata from the Eastern Cordillera (EC) and the Cucuta zone, at the junction between the Santander Massif and the Merida Andes of Colombia. The EC is an intracontinental doubly vergent range inverting a Triassic to Early Cretaceous rift zone. Twenty-three sites reveal nonsystematic tectonic rotations, including unrotated areas of the EC range with respect to stable South America. Our data show that the EC inverted a NNE oriented rift zone and that the orientation of the Mesozoic rift and the mountain chain roughly correspond. Interestingly, magnetic lineations from anisotropy of magnetic susceptibility analysis do not trend parallel to the chain but rather are oblique to the main orogenic trend. By also considering GPS evidence of a~1 cm/yr ENE displacement of central western Colombia accommodated by the EC, we suggest that the Miocene-Recent deformation event of this belt arises from ENE oblique convergence reactivating a NNE oriented rift zone. Oblique shortening was likely partitioned into pure dip-slip shear characterizing thick-skinned frontal thrust sheets (well known along both chain fronts) and by range-parallel right-lateral strike-slip faults, which have not been identified yet, but likely exist in the axial part of the EC. Finally, the 35°± 9°clockwise rotation observed in four post-Miocene magnetically overprinted sites from the Cucuta zone reflects late Cenozoic and ongoing right-lateral strike-slip displacement occurring along faults parallel to the Boconó fault system, possibly connected with the right-lateral faults inferred to exist along the axial part of the EC.

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