considerations. The equilibriiom slope was a function of the angle of repose 

 and the ratio between energy losses at the bed during offshore- and onshore - 

 directed flow. 



43. Eagleson, Glenne, and Dracup (1963) studied equilibrium profiles in 

 the region seaward of the influence of breaking waves. They pointed out the 

 importance of bed load for determining equilibrium conditions and used 

 equations for particle stability to establish a classification of beach 

 profile shapes. 



44. Iwagaki and Noda (1963) derived a graphically presented criterion 

 for predicting the appearance of bars based on two nondimensional parameters, 

 deepwater wave steepness, and ratio between deepwater wave height and median 

 grain size. The change in character of breaking waves due to profile evolu- 

 tion in time was discussed. The potential importance of suspended load was 

 recognized and represented through the grain size, this quantity emerging as a 

 significant factor in beach profile change. 



45. Zenkovich (1967) presented a summary of a number of theories 

 suggested by various authors for the formation of bars . 



46. Wells (1967) proposed an expression for the location of a nodal 

 line of the net cross -shore sand transport based on the horizontal velocity 

 skewness being zero, neglecting gravity, and derived for the offshore, outside 

 the limit of breaking waves. Seaward of the nodal line material could erode 

 and shoreward -moving sand could accumulate, depending on the sign of the 

 velocity skewness. 



47. Berg and Duane (1968) studied the behavior of beach fills during 

 field conditions and suggested the use of coarse, well -sorted sediment for the 

 borrow material to achieve a more stable fill. The mean diameter of the 

 grains in the profile roughly decreased with depth, with the coarsest material 

 appearing at the waterline (Bascom 1951, Scott 1954). 



48. Mothersill (1970) found evidence through grain size analysis that 

 longshore bars are formed by plunging waves and a seaward -directed undertow 

 (Dally 1987). Sediment samples taken in troughs were coarser, having the 

 properties of winnowed residue, whereas samples taken from bars were finer 

 grained, having the characteristics of sediments that had been winnowed out 

 and then redeposited. 



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