The Eastern Frontal Fault System (Spanish: Sistema de Fallas de la Falla Frontal de la Cordillera Oriental) is a megaregional system of oblique and thrust faults cross-cutting Colombia from Ecuador in the south to Venezuela in the north. The system from south to north covers ten out of 32 departments of Colombia; Nariño, Putumayo, Cauca, Huila, Caquetá, Cundinamarca, Meta, Boyacá, Casanare and Arauca. The Eastern Frontal Fault System underlies and affects the capitals of Putumayo, Mocoa, Caquetá, Florencia, Meta, Villavicencio and Casanare, Yopal. The fault system has a total length of 921.4 kilometres (572.5 mi) with a cumulative length of the faults of 1,821.8 kilometres (1,132.0 mi) and runs along an average northeast to southwest strike of 042.1 ± 19 bordering and crossing the Eastern
