The fault system with described segments totalling almost in length comprises several parallel regional fractures (faults) that form the transition zone between oceanic rocks to the west and continental rocks to the east. The geology of the western domain consists of an ophiolitic belt with oceanic gabbroic, basaltic and sedimentary rocks of Cretaceous age. The eastern domain consists primarily of continentalised metamorphic schistose, oceanic, and continental rocks, mainly of Paleozoic age. The Romeral Fault System forms a wide deformed belt that is parallel to the western slope of the Central Ranges of the Colombian Andes; it extends from the Gulf of Guayaquil in Ecuador in the south through Colombia to the Caribbean Sea in the north. At least one ancient subduction zone is believed to underlay some parts of the zone. Although this is the most studied fault system in Colombia, little is still known about its paleoseismic characteristics (most recent faulting, slip rates, and recurrence intervals). Parallel to the Romeral Fault System runs the Cauca-Pujilí Fault that also extends into Ecuador in the south. The two fault zones converge in the northern part of the Cauca Basin.