Sediment Slides on the Northwestern Continental Margin of Africa.

摘要

A sediment slide complex has been mapped on the West African continental margin north of Dakar, Senegal. Four major slides covering approximately 44,300 sq km were delineated by seismic reflection profiles, 3.5 and 12 kHz echograms and piston cores. Although the slide areas have been altered by later erosion and deposition by turbidity flows, the major components of the slides-slide scar, zones of hummocky and blocky slide material and zones of debris flow-are recognizable. Cores containing flow folds with horizontal axial surfaces substantiate the echogram interpretations of debris flow. Morphology and depositional areas of the slides indicate that several major slide movements have occurred in each of the various slide areas. The triggering mechanism for these slides is perhaps earthquakes associated with the Cape Verde Islands, Cape Verde Plateau, and adjacent fracture zones. (Author)