Boletín de Ciencias de la Tierra
Print version ISSN 0120-3630
RESTREPO C., ISABEL CRISTINA; OJEDA B., GERMAN Y. and CORREA A., IVÁN DARIO. GEOMORPHOLOGY OF THE DEPARTAMENTO DE CÓRDOBA INNER SHELF, COLOMBIAN CARIBBEAN COAST. Bol. cienc. tierra [online]. 2007, n.20, pp. 39-52. ISSN 0120-3630.
The inner (less than 10 m depth) continental shelf in front of Department of Córdoba extends from 8º 52´58 N, 76º 24´53 O to 9º 2042 N, 75º 47 55 O, just south of Gulf of Morrosquillo, Colombian Caribbean Coast. In order to get a general picture of the morphology and subbottom geometry of the area, a set of 140 bathymetrical and geophysical (200 and 12 kHz) transects were collected both perpendicular and parallel to the shoreline. The morphology of the area in the southern and central zones (from Arboletes to Tinajones delta) resembles that of an extended surface of marine erosion with a rather uniform topography, characterized by concave-upward depositional surfaces down to the -8m isobath, (minimum slopes in the order of 0.01494 %) and a well defined, concave, erosional surface at shallower depths (maximum slopes of the order of 1.88 %) on which recent and present transgressive conditions are well evidenced by numerous wave-cut platforms and by the strongly erosional character of beaches and cliffs along most of the 124 km-long coastline. The morphology of the eastern inner shelf (from the Sinú delta-Cispatá Bay-Punta Bolívar) is highly variable and characterized to the west by two prograding prisms (Tinajones and Los Venados deltas), terraced surfaces, other positive reliefs (¿paleoreefs?, ¿mud volcanoes?) and a series of steep scarps (at depths of -4m, -6m, and -10m) suggesting ancient submerged shorelines. High resolution records (12 kHz) of the area show highly dynamical and unstable environments affected during the late Holocene by mud diapirism, active faulting and depositional events (up to 5m thick) that filled ancient channels and small basins.
Keywords : Colombia; Continental shelf; Holocene; Marine geophysics; Mud diapirism; Shore erosion.