NONUNIFORM ALONGSHORE SEDIMENT TRANSPORT INDUCED BY COASTLINE CURVATURE

Alejandro López-Ruiz, Miguel Ortega-Sánchez, Asunción Baquerizo, David Navidad, Miguel Ángel Losada

Abstract


This work proposes an expression for the alongshore sediment transport and a one-line type model to analyze the importance that the curvature of the shoreline and the bathymetric contours, and the associated alongshore wave energy gradients have in the evolution of the coastline and in the development of shoreline undulations. This model characterizes the alongshore wave energy gradients by means of the surf zone width variations and does not make any restriction on the shoreline curvature. The shoreline undulations of two different types of coast are investigated: a curvilinear coast in a prograding spit front, and an erosional stretch of coast adjacent to a river mouth. The results for the first one are in good agreement with observations. For the erosional coast good qualitative results are obtained, although a more intensive study is required.

Keywords


Alongshore sediment transport; shoreline curvature; shoreline undulations

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