Deformation partitioning in the Llanos foreland basin during the Cenozoic and its correlation with mountain building in the hinterland

Previous studies have argued that deformation in foreland basins is either controlled by inherited structures, is a direct response to the advancing orogenic load or is a combination of these two factors. To provide insights into the relative importance of these processes in foreland basin development, we generated an inventory of syn-kinematic relationships for the Llanos foreland of Colombia using an extensive (∼5000 km) network of 2D seismic lines. The results of this work indicate that most of the Miocene extensional deformation in the central Llanos trends parallel to the orogen and follows the propagation of orogenesis to the east. Thus, the dominant control on deformation of the Llanos foreland basin is related to flexure during episodes of enhanced orogenic load. This observation is fundamental to understand the nature of deformation in continental interiors and cratonic areas in front of active orogens.