data were taken during the preceding 24-hr period of profile survey, the wave 

 data can be considered influential in the deposition of the particular sedi- 

 ment deposited on the profile on that day. The measure of erosion or accre- 

 tion was based on anywhere from 2 days to over a month between profiles; thus 

 there was not a good agreement of determined erosion and accretion with the 

 theoretical values. Since all but three of the profiles had a general inner 

 bar shape, the criterion of bar or berm profile shape was not a good delimiter 

 of erosion or accretion. 



57. The main point of this part of the study was to show that the 

 choice of grain-size data to use in the calculation of the sediment fall 

 velocity is important to the use of this criterion. Coarse berm sediment 

 means or medians will shift the point to the left toward an accretional mode, 

 while the use of finer means or medians such as were found in the nearshore 

 composites shifted the data to the erosional side of the plot. The use of a 

 profile composite seemed to fit the criteria of Kraus (1990) the best. The 

 location on the profile of median grain- size data used in Kraus (1990) was not 

 specified. The composite profile sediment data set using the FRF data fell 

 between the beach and nearshore data and basically averaged the grain- size 

 median or mean over the entire cross -shore distance. 



58. It is suspected that in the past most sediment data have been col- 

 lected on the subaerial beach, but the original criterion H /wT was devel- 

 oped by Dean (1973) , who based the settling velocity of the grains on the area 

 of location under the breaker. The formation of a bar- type profile is usually 

 dependent on transport of sand from the beach foreshore out to the nearshore 

 bar position. Movement of sand by bar migration onto the lower foreshore with 

 berm growth characterizes accretion. Swash processes dominate the transport 

 on the foreshore, while turbulent interactions of wave and current- induced 

 transport characterize the dominate processes over the nearshore bar. More 

 research needs to be done on the correct choice of median (or mean) grain size 

 to use in predicting erosion or accretion, owing to the fact that the grain- 

 size distribution varies across the profile depending on the mode of transport 

 common to that area. 



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