Table 4. Comparison of Mean Grain Size and Standard Deviation for 

 Sands from Potential Borrow Areas and Beach Profiles 



Offshore Borrow Area Sands 



Potential Borrow Area 



Mean Size 

 (Median) 



Standard Deviation 



(mm) 



(0) 



■ (mm) 



(0) 



The Bull 



0.28 to 0.51 

 0.29 to 0.66 



1.83 to 0.97 

 1.80 to 0.74 



0.67 to 1.82 



0.58 to 0.86 



Ohio-Hetzel Shoal 



0.27 to 0.73 

 0.29 to 0.68 



1.87 to 0.46 

 1.81 to 0.57 



1.20 to 2.32 



0.26 to 1.21 



Chester Shoal 



0.39 to 0.67 



1.35 to 0.57 



0.65 to 0.73 



0.62 to 0.44 





0.39 to 0.69 



1.36 to 0.58 







Southeast Shoal 



0.31 to 0.77 

 0.33 to 1.12 



1.69 to 0.37 

 1.62 to 0.17 



1.46 to 2.1 



0.54 to 1.07 



Canaveral Beach Profile Sands 



Position on Profile 



Median Size 





(mm) 



(0): 



Dune 



0.38 



1.39 





Dune to MHW 



0.38 to 0.49 



1.39 to 1.00 





MLW 



0.42 



1.25 





Depths of 3, 6, and 12 ft. 



0.13 to 0.22 



2.95 to 2.18 





Depths of 18 and 30 ft. 



0.29 to 0.36 



1.72 to 1.48 





c. Potential Borrow Areas. Approximately 60 X 10* cubic yards of Type A sand he in 

 the Cape Canaveral grid at thicknesses of over 5 feet. (See Figure 21.) This computation, 

 based on core data, indicates a minimum volume of sand available as a borrow source since 

 the total sand thickness was not always penetrated. 



Four areas are suited as borrow sources based on their textural similarities with areal 

 beach sands and the known consistent thickness of the deposits. These potential borrow 

 areas (Fig. 26) are: Chester Shoal, Southeast Shoal, The Bull and Ohio-Hetzel Shoal. Photos 

 of representative samples from three of the shoal areas are shown in Figure 24. Figures 27 

 through 34 show detailed bathymetry and representative geophysical profiles of each shoal. 

 The blue reflecting horizon is the base level for computations of maximum volume of 

 suitable sand; minimum volumes are computed to the first sonic or Uthologic change. 

 Textural and mineralogic properties of sediments comprising the blue layer indicate it is 

 unsuited for use in beach nourishment. 



Chester Shoal was not completely surveyed and no attempt has been made to estimate its 

 total reserves. The volume Qf sand suitable for recovery from the part of Chester Shoal 

 shown in Figure 27 is judged to be 8.8 X 10* cubic yards; if suitable material extends to the 

 blue horizon, reserves are more than 93 X 10* cubic yards. The blue horizon hes at 20 to 40 

 feet beneath the bottom in this area. (See Figure 28.) Cores 164, 165, and 166 contain 

 suitable material to depths of 7, 8, and 12 feet, respectively; no samples below 12 feet are 

 available for analysis. 



56 



