SOME SAND TRANSPORT PHENOMENA OH COASTS WITH BARS

Abstract

Longshore wave currents and their influence on the sand transport phenomena m the shore zone have attracted the attention of numerous researchers. Also the existence of transverse, secondary currents, superposing the longshore component, has been known for years, but less attention has been given to analysis of their effect on the sediment movement. This paper presents some examples of the influence, these relatively weak transverse currents may have on the processes in the shore zone. They have a parallel in the effect of secondary currents in alluvial streams, which, although weak, give use to such an impressive phenomenon as meandering. All conclusions below are based on simple, qualitative considerations of the physics of the system. A strict mathematical, quantitative approach to the problem does not seem possible with the present knowledge of the fluid dynamics in the shore zone, and much further research into these complex phenomena remains, of course, necessary.