SEDIMENT TRANSPORT PREDICTIONS FOR THE ENGLISH-CHANNEL, USING NUMERICAL-MODELS

Output from an hydrodynanmic numerical model (Salomon & Breton 1991a, b) has been combined with various empirical formulae to derive sedimen t transport rates and directions. The predictions are compared with ra dioactive sand tracer experiments, demonstrating the applicability of Gadd et al.'s (1978) expression. The derived bedload transport pattern for the area is consistent with sedimentological and geomorphological evidence, but provides improved resolution. A 'bedload parting zone' is identified for the central English Channel; this is well defined fo r sand movement, but seabed material present over this area (gravel) i s not predicted to move significantly. The area is 'non-erosive', over which fine-grained sediments are being transported. A bedload converg ence is located to the southwest of the Dover Strait, not in the Strai t itself as proposed previously. A transport pathway, bypassing the co nvergence, along the French coastline (which is supported by radioacti ve tracer experiments) could be responsible for sand transfer from the English Channel to the southern North Sea.