SEDIMENTARY ENVIRONMENTS/Shoreline and Shoreface Deposits 579 Figure 10 Geographical features of a high relief erosional coastline (Figure 10) Changes in relative sea-level may lead to the formation of wave-cut terraces or marked wave-cut notches The geomorphological character of a cliff is a product of the bedrock geology and the climate Hard, resistant bedrock will result in high, steep cliffs that retreat slowly and show pronounced wave-cut notches at the base; softer deposits will result in lower, less steep, rapidly retreating clifflines The process of cliff retreat is enhanced in a wetter climate and is retarded in more arid regions The wave-cut platform is a horizontal to low-angle seaward-dipping surface that occurs between mean high watermark and wave base The wave-cut platform may be covered in a thin veneer of reworked sediment or may be bare Where present, sediment may range in grain size from sand particles to boulders Clasts are generally well rounded due to frequent reworking by waves Wave movement of the retreating cliffline-derived sediment is a key process in the scouring of the platform As erosional features, rocky coastlines have little preservation potential in the geological rock record, although they may account for significant amounts of geological time Preservation will be limited to an erosional surface that records the final position of the shoreline prior to a change in conditions that led to the onset of deposition Immediately above this surface a thin veneer of sediment may be preserved See Also Sedimentary Environments: Carbonate Shorelines and Shelves; Storms and Storm Deposits Sedimentary Processes: Fluvial Geomorphology Further Reading Boyd R, Dalrymple RW, and Zaitlin BA (1992) Classifica tion of clastic coastal depositional environments Sedimentary Geology 80: 139 150 Coe A (ed.) The Sedimentary Record of Sea Level Change Cambridge: Cambridge University Press Clifton HE, Hunter RE, and Phillips RL (1971) Depos itional structures and processes in the non barred high energy nearshore Journal of Sedimentary Petrology 41(3): 651 670 Davidson Arnott RGD and Greenwood B (1976) Facies relationships on a barred coast, Kouchibouguac Bay, New Brunswick, Canada Beach and Nearshore Sedimen tation SEPM Special Publication No 24, pp 149 168 Tulsa, OK: Society for Sedimentary Geology Davis RA and Fitzgerald DM (2004) Beaches and Coasts London: Blackwell Science Davis RA, Fox WT, Hayes MO, and Boothroyd JC (1972) Comparison of ridge and runnel systems in tidal and non tidal environments Journal of Sedimentary Petrology 40(2): 413 421 Dominguez JML, Bittencourt ACSP, and Martin L (1992) Controls on Quaternary coastal evolution of the east northeastern coast of Brazil: roles of sea level history, trade winds and climate Sedimentary Geology 80: 213 232 Elliott T (1986) Clastic shorelines In: Reading HG (ed.) Sedimentary Environments and Facies, pp 143 177 London: Blackwell Scientific Publications Heward AP (1981) A review of wave dominated clastic shoreline deposits Earth Science Reviews 17: 223 276 Walker RG and Plint GA (1992) Wave and storm dominated shallow marine systems In: Walker RG and James NP (eds.) Facies Models: Response to Sea Level Change, pp 219 238 Ottawa: Geological Society of Canada