Summary: | Bibliography: pages 128-130. === This thesis consists of three parts. In Part One a literature study is made of available knowledge regarding wave theory and sediment transport in the nearshore zone, with special emphasis on littoral drift. The linear Airy theory for water waves is developed for the computation of longshore current, utilizing certain exact relationships for momentum flux. The near shore beach environment is discussed in detail with regard to the wave forces acting on it, beach forms, and three-dimensional circulation patterns. Part Two deals with experiments conducted in the hydraulics laboratory, Department of Civil Engineering, University of Cape Town, using the existing model wave basin. The experimental programme covers the development of equilibrium beach profiles as a function of certain wave characteristics, and seeks the relationship between different profiles in terms of the wave characteristics that formed them. Both normal and oblique wave attack programmes are reported on, the latter in terms of existing known relationships for littoral drift. Part Three deals with experiments conducted in the field off the South West African coast. Beach profile changes are compared to the local wave climate and relationships are sought between these changes and certain wave characteristics. A fluorescent tracer study on the swash zone is reported on as a method of gauging littoral drift.
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