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  • Print publication year: 2016
  • Online publication date: June 2016

13 - Sandy coasts

Summary

Abstract

The South African coastline is variable in geomorphic character, but at least two thirds of the coastline is dominated by sandy and part-lithified sandy intertidal shorelines. Part-lithified sandy intertidal shorelines consist of a mosaic of rocky outcrops on dominantly sandy beaches. The rocks on these mixed shores are generally composed of cemented Quaternary deposits. Carbonate cemented Quaternary aeolianite/beachrock complexes are relatively common along the South African coastline and on the continental shelf, where they form prominent reefs. The Quaternary deposits along the coastline are characterised mainly by transgressive dune cordons. These systems record sensitive palaeoenvironmental fluctuations, as archived in their structure, diagenetic history, and relationship to past sea-levels and ancient shorelines.

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