Browsing by Author "Franceschini, Giuliana"

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    Geology of Aeolian and marine deposits in the Saldanha Bay region, Western Cape, South Africa
    (2003) Franceschini, Giuliana; Compton, John; McMillan, Ian K; Rogers, John
    The west coast of South Africa has been exploited for diamonds for most of the last century. Although some literature has accumulated over this period, the evolution of the coastal plain since the Cainozoic remains poorly understood. The aim of this thesis is to offer a multidisciplinary study of the evolution of coastal deposits in the Saldanha Bay area, along the southern part of the west coast. The environments investigated comprise lagoons, coastal dunes and shorelines. The ages of the deposits were obtained with radiocarbon dating, strontium isotope stratigraphy and biostratigraphy.
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    Sand transport along the Western Capecoast: Gone with the wind?
    (2003) Franceschini, Giuliana; Compton, John S; Wigley, Rochelle A
    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.