the shell material and alongshor? variations in factors controlling sedi- 

 ment distribution and shell supply. The coarsest material, for example, 

 occurs near inlets or close to outcrops of the Anastasia Formation where 

 large quantities of shell are available. As shell is moved away from 

 these source areas, it may be reduced by mechanical and chemical degra- 

 dation and is diluted by an increase in finer quartzose material. 



In deeper nearshore water (from -21 to -30 feet MLW), material com- 

 posing the bottom surface is finer, better sorted and far more uniform 

 in size than the sediment in shallower water nearer shore. These deeper 

 shoreface deposits probably result from the classic sedimentation model 

 of seaward transport of finer particles winnowed from the sands in high- 

 energy surf zone; deposition of the fines occurs in quieter water. The 

 few samples available from the outer nearshore zone are richer in quartz, 



Median diameter of foreshore beach samples from the study area are 

 mostly between 0.3 and 0.5 millimeters (1.74 to 1.0 phi). This, then, 

 is the approximate range of median sizes required in a normally sorted 

 borrow material which would be most suitable for fill sand to nourish 

 eroding beaches in the study area. 



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