Volumetric analysis of residual sediments migrations on Continental Shelf sand banks in the Southern Bight (North Sea)

Sediment transport results in erosion and deposition and therefore in changes of form, location and volume of seabottom structures, especially sandbanks. These changes can be studied over several time intervals. Residual sedimentdynamics concern net sediment migrations over longer periods as resulting from successive short time direction and intensity varying displacements. In an environment with high sediment migration variations, residual sedimentdynamics can be approached by geomorphological techniques. The paper analyses the residual sedimentdynamics on the Flemish Banks over the period 1983-1988 on the ground of a monitoring of volumetric changes of sand banks along fixed reference profiles. The monitoring departs from sequential detailed bathymetric profiling along the refernce tracks, high precision navigation and positioning and profile normalisation to make successive data comparable, using appropriate software equipment. Sequential profiling at a 1 mile distance allows bank covering over one tidal cycle