The stratigraphy of the Middle Magdalena Basin can be divided into three sequences separated by angular unconformities. The basement of these sequences is Pre-Mesozoic metaclastics and sediments which are now exposed on the surface of the Central Cordillera as a result of its deformation and uplift. This geologic basement is at most deep, with faulted sections shifted up to approximately in depth. The unconformity that separates the basement from the first sequences indicates the approximate time rifting began.