See more from this Division: Topical Sessions
See more from this Session: Coastal and Aeolian Geomorphology Processes and Landforms
Abstract:
Field surveys documented bimodal, topographically-controlled ebb-tidal flow over the flood-tidal delta. Bedforms were oriented between 60-75° oblique to the direction of unobstructed ebb-tidal flow. The ebb-tidal prism could not be accommodated in the main tidal channel thus increasing the hydraulic slope and allowing water to flow over the flood-tidal delta.
The links between the two-dimensional morphology of the flood-tidal delta and the inlet are clear. A feedback mechanism linking the flood-tidal delta with the migration of the main ebb channel was documented in the study area. The main ebb channel of the inlet migrates downdrift as material entrained in the longshore sediment transport system becomes incorporated into the swash platform. The size of the flood-tidal delta increases as growth of the swash platform allows more sediment to enter the harbor. As the surface area, and particularly the width, of the flood-tidal delta increases the ebb-tidal flow is restricted which results in narrower and deeper ebb channels. This channelization of ebb-tidal flow increases the shallower areas in the harbor increasing the sediment transport during flood-tidal flow thus continuing the cycle.
See more from this Division: Topical Sessions
See more from this Session: Coastal and Aeolian Geomorphology Processes and Landforms