The Magdalena Turbidite System (Caribbean Sea): present-day morphology and architecture model

A detailed analysis of the modern morphology, acoustic facies and architecture of the eastern Magdalena Turbidite System has been based on multibeam bathymetry and backscatter data, In spite of the fact that the Magdalena Turbidite System developed in a tectonically active setting, its present architecture model is comprised of two tecto-sedimentary provinces: deformed-constructional and undeformed-erosive. The deformed province occurs where the deformed prism developed. This prism is characterised by structural highs and associated small-scale ridges and scarps. In this province, the Magdalena Turbidite System is constructional because sediment coming from the Colombian hinterland (via the Magdalena River and from coastal erosion) and sediment remobilised from the walls of the structural highs are transported trough canyons and gullies, and emplaced as gravity deposits into the deformed prism. In the undeformed province, by contrast, the Magdalena Turbidite System displays an architecture model similar to a passive continental margin, and is characterised by large-scale mass-flow deposits, leveed channel complexes, scars of stumps, and sediment waves. This province is presently erosive because the existing leveed channels are partially or totally destroyed and cannibalised by mass-flow deposits, cut by small-scale scars of slumps, and their morphology is subdued or modified by the formation of a sediment wave field. (C) 2002 Elsevier Science B.V All rights reserved.