We use the Eastern Cordillera of Colombia as an example in early stages of inversion orogen showing still modest values of shortening. The style of deformation recorded in this orogenic chain seems to be strongly influenced by two main factors. The first is the pre-compression geometry of the rift basin, conditioning the strong heterogeneity imparted by a trough filled with Jurassic to Neocomian sediments limited by Precambrian and Palaeozoic high-angle walls. The second factor is the orientation of the stress regime with respect to the main normal faults during the inversion. If the stress field is of pure compression, the normal faults are not extensively inverted and the deformation is accommodated mainly in terms of footwall shortcuts. On the other hand, in transpressive regimes the inversion of the former normal faults is more common and the footwall shortcuts are not dominant structures. No significant lateral variations in tectonic shortening are found in the Eastern Cordillera. Finally we emphasize the role of buckle folds in the internal parts of the inversion orogens and give a cautionary note when interpreting these structures in terms of fault-related folding using the well-documented example of the Soapaga fault area.

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The Magdalena Valley fold-and-thrust belt is a tectonic province associated with inverted rift zones. This belt displays a narrow and discontinuous deformation front indicating association with inversion tectonics. We show the differences with an analogue belt on the eastern side of the Eastern Cordillera (Llanos foothills). To do that we use structural data (seismic, wells and geological maps) which characterize different structural geometries as well as palaeocurrents, provenance and thermochronology to analyse the timing of deformation. The new datasets allowed us to detect that inversion is limited whenever the stresses are more orthogonal to the rift structures, whereas the mountain front is more segmented in comparison to the Eastern Foothills because of the absence of a continuous low basal friction detachment horizon and a pronounced eastwards basement dip. These two factors favoured fault hard linkage. It is remarkable that, in spite of the distinct segmentation, all the different segments in the Magdalena belt are coeval.Supplementary material:U–Pb Zircon data are available at: http://www.geolsoc.org.uk/SUP18630.

The geometry, kinematics and evolution of thick- and thin-skinned fold and thrust-belts have been characterized for many tectonic provinces. However, the impact of prior extension in the structural evolution of fold and thrust-belts remains under-appreciated. We use a series of balanced cross sections across areas of thin- and thick-skinned tectonics superimposed over former extensional structures in order to characterize the style of deformation, segmentation and displacement magnitude. We detect the style of fault linkage in foothill settings adjacent to inversion belts. The most relevant aspect is the presence of inherited ‘soft linkages’ generating zones of displacement deficit, which in contraction interact laterally with en-echelon inverted segments via ‘detachment linkages’. We document the temporal development and interaction between inverted faults and fault splays branching from them where both are coeval but where the frontal fault tips propagate more slowly during Oligocene and Early Miocene times. Later, during the Neogene, the frontal fault splays slip faster than the main inversion fault. The structural style of thrust-belt development displays along-strike variations, which reflect the changes in sedimentation rates and mechanical conditions of deformation. However, the timing and magnitude of shortening remain uniform along-strike.

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