161. SILVESTER, R., "Stabilization of Sedimentary Coastlines," Nature^ 

 Vol. 188, No. 4749, Nov. 1960, pp. 467-469. 



Keywords: Accretion, Artificial headlands, Crenul ate -shaped bay. 



Hydraulic model (three-dimensional). Littoral transport, 

 Movable bed, Tombolo 



A sedimentary coastline with a predominant direction of swell tends 

 to develop crenulate-shaped bays between adjacent headlands. This has 

 been verified by model experiments described here. The use of artificial 

 headlands would stabilize eroding shorelines by promoting growth of min- 

 iature crenulate-shaped bays, providing wide beaches to protect backshore 

 areas . 



162. SILVESTER, R., "Sediment Movement Around the Coastlines of the 

 World," Proceedings of the Conference on Civil Engineering Problems 

 Overseas^ Institution of Civil Engineers, 1962, pp. 14-1--14-15. 



Keywords: Artificial headlands, Crenulate-shaped bays. Hydraulic model 

 (three-dimensional), Littoral transport, Movable bed 



Ocean waves and their action on beaches are discussed with emphasis 

 on the two classifications, storm and swell, and on the repetitive nature 

 of their occurrence. Discussion of beach processes explains the impor- 

 tance of the persistent swell in sediment movement. 



A model investigation is described in which waves from an oblique 

 direction eroded a straight sedimentary coastline until a stable bay 

 shape was formed about fixed headlands, A similar shape was seen to 

 occur in nature as is observed, for example, on Admiralty Charts. The 

 orientation of these bays was related to the direction of the predominant 

 swell and hence of the net sediment movement along the coast. Sediment 

 movement for the coastlines of the world was determined from the Admiralty 

 Charts. The significance of such data for the design of maritime struc- 

 tures is discussed. 



163. SILVESTER, R., "Beach Profiles and Littoral Drift Assessment," 

 La Houille Blanche ^ Grenoble, France, Vol. 24, No. 6, 1969, pp. 

 615-621. 



Keywords: Artificial headlands, Crenulate-shaped bay. Littoral transport. 

 Sand tracer study. Wave refraction 



Typical or standard beach profiles, if established for a given wave 

 climate and sediment characteristic, could be useful for measuring sta- 

 bility. The balance of volumes in a storm and swell profile would permit 

 the assessment of imminent beach degradation. The many formulas derived 

 for littoral current and littoral drift need attention as also the many 

 practical variables involved in their measurement. Greater cognizance 

 should be taken of sediment transport offshore from the surf zone. 



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