49. Sonu (1969) distinguished six major types of profiles and described 

 beach change in terms of transitions between these types. 



50. Edelman (1969, 1973) studied dune erosion and developed a quantita- 

 tive predictive procedure by assuming that all sand eroded from the dune was 

 deposited within the breaker zone. On the basis of a number of simplifying 

 assumptions, such as the shape of the after -storm profile being known together 

 with the highest storm surge level, dune recession as produced by a storm 

 could be estimated. 



51. Sonu (1970) discussed beach change caused by the 1969 hurricane 

 Camille, docvimenting the rapid profile recovery that took place during the end 

 of the storm itself and shortly afterward (see also, Kriebel 1987). 



52. Nayak (1970, 1971) performed small-scale laboratory experiments to 

 investigate the shape of equilibrium beach profiles and their reflection 

 characteristics. He developed a criterion for the generation of longshore 

 bars that is similar to that of Iwagaki and Noda (1963) but included the 

 specific gravity of the material. The slope at the still-water level for the 

 equilibrium profile was controlled more by specific gravity than by grain 

 size. Furthermore, the slope decreased as the wave steepness at the beach toe 

 or the dimensionless fall speed (wave height divided by fall speed and period) 

 increased. The dimensionless fall speed was also found to be a significant 

 parameter for determining the reflection coefficient of the beach. 



53. Allen (1970) quantified the process of avalanching on dune slopes 

 for determining the steepest stable slope a profile can attain. He introduced 

 the concepts of angle of initial yield and residual angle after shearing to 

 denote the slopes immediately before and after the occurrence of avalanching. 



54. Dyhr -Nielsen and Sorensen (1971) proposed that longshore bars were 

 formed from breaking waves which generated secondary currents directed toward 

 the breaker line. On a tidal beach with a continuously moving break point, a 

 distinct bar would not form unless severe wave conditions prevailed. 



55. Saylor and Hands (1971) studied characteristics of longshore bars 

 in the Great Lakes. The distance between bars increased at greater than 

 linear rate with distance from the shoreline, whereas the depth to crest 

 increased linearly. A rise in water level produced onshore movement of the 

 bars (cf. Evans 1940). 



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