A bathymetric, magnetic, and seismic profiler survey of the Caribbean Sea north of Colombia revealed four natural geologic systems: (1) a Quaternary erosional system of continental shelf modification and submarine canyon formation; (2) a sedimentological system of seaward progradation of the continental shelf and slope and of turbidite deposition in basins; (3) a deformational system with a fold belt flanking the continent and faults marking the coast; and (4) the ocean-continent transition. The deformation system severely modifies the sedimentational system and is penecontemporaneous. The fold belt acts as a dam to a marginal, turbidite-filled basin. The east-west magnetic pattern of the Colombian basin contrasts with the less intense anomaly pattern paralleling and associated with the continental margin. The geological evidence indicates that the continent is decoupled from the Colombian basin, and that a relative east-west movement exists.