Mesozoic-Cenozoic sedimentation in the Cameros Basin area strongly reflects tectonic factors. The tectonic history is dominated by two principal extensional phases (Triassic, Late Jurassic-Early Cretaceous) and strong Pyrenean compression (Oligocene). Late Variscan NW-SE and NE-SW fault sets were repeatedly reactivated as dip-slip and wrench faults respectively throughout extension and compression. E-W Variscan thrust planes showed relatively minor reactivation in this area.
Mesozoic fault control on sedimentation resulted in significant lateral variations in stratigraphic and sedimentological development. Variation in deformation style and thrust architecture reflects the differing responses of the laterally heterogeneous sequence to Oligocene compression.