Geology of the Cabuérniga Fault System: evolution of a large Alpine structure with Variscan inheritance

The Cabuérniga Fault System (CFS) extends for 150 km in E–W trend along the northern divide of Cantabrian Mountains, near Sea. This fault system was reactivated several times since Paleozoic, and displays hydrothermal activity nowadays. We present here a detailed geological map whole CFS six cross-sections distributed strike, which allowed us to unravel kinematic history individual segments comprising CFS. current geometry mainly results from reactivation Variscan thrusts NW–SE Late-Variscan strike-slip faults during Alpine Cycle. Reactivation took place relation both Permian Mesozoic pre-orogenic extension subsequent Cenozoic shortening. eastern end corresponds N–S structure arriving at coast, while western edge connects with trending Llanera fault, leading an extending 220 km.