The use of the McLaren Model for the determination of residual transport directions on the Gootebank, Southern North Sea

Sixty samples were collected on the Gootebank to assess the application of the McLaren sediment transport model on a tidal sandbank environment. Residual sediment transport directions were deduced and compared with the results of a detailed bedform analysis obtained by side-scan sonar recordings. Results show that when sediments become finer and better sorted, the corresponding skewness becomes more positive which is in contradiction with the sediment transfer function of McLaren and Bowles (1985). Comparison of the directions of residual sediment transport deduced from bedform analysis and from the sediment trend analysis shows that a good similarity is reached in the adjacent swales and that an offset of 90° exists on the bank. The transversal grain-size differentiation is explained by the formation of a lag deposit induced by an upslope increase in maximum current speed from the swale to the bank crest