Sand transport along the Western Capecoast: Gone with the wind?

Franceschini, Giuliana; Compton, John S; Wigley, Rochelle A

Sand transport along the Western Capecoast: Gone with the wind?

Journal Article

2003

Journal Title

South African Journal of Science

Link to Journal

https://www.sajs.co.za/

Publisher

University of Cape Town

Department

Department of Geological Sciences

Faculty

Faculty of Science

Abstract

Beach sand sample were collected between Cape Town and St Helena Bay in order to study sediment composition and transport along the Western Cape coastline. Between Cape Town and Saldhana Bay, the beaches are a mixture of terrigenous and carbonate material. Those between Saldanha Bay and Shelley Point are carbonate-rich. North of Shelley Point, terrigenous-rich beaches were found. The decrease in terrigenous material from Cape Town to Saldanha Bay is a reflection of reduced delivery of terrigenous sand by rivers. The low content of terrigenous material in beach sands between Saldanha Bay and Shelley Point is related to the high biogenic CaCO3 in the rocky coastal area. In St Helena Bay the high percentage of terrigenous material is contributed by the Berg River. Coastal dune composition also reflects the mineralogy of the beach sand. This work indicates that the terrigenous material delivered by rivers to False Bay and Table Bay move northwards by longshore drift while being mixed with carbonate shell fragments.