Surficial sediments in the Cape Canaveral grid are primarily medium-to-coarse, well-sorted 

 quartzose-mollusk sand, varying in thickness from 1 to 13 feet; in places the sand may be 

 40 feet thick. Areal distribution and thickness of this modern sand is closely related to 

 topography; deposits are thickest beneath topographic highs, generally less than 5 feet thick 

 on flat areas, and absent in depressions. Sediments in the survey area are both rehct and 

 modern; the latter derived from reworking of the former and are described as palimpsest 

 sediments. The subsurface, partially both the Pleistocene sediment which occasionally crop 

 out and the mid-Holocene transgressive relict coastal sediments, have been reworked by 

 physical and organic processes and reshaped to form an undulatory surface of active 

 palimpsest sediments. Late Quaternary and modern deposition has centered around the 

 large, south-trending, shore-connected shoals. The large plano-convex isolated shoals lying 

 seaward of cape shoals, particularly The Bull, are judged to represent remnants of earUer 

 shore-connected shoals that were segmented and stranded during a sea level rise and the 

 concomitant coastal and shoal retreat. 



Area beach sediments contain fine-to-coarse quartz and shell sand. Individual beaches 

 vary in proportions of these two components and there is a direct relationship between 

 increase in shell content and increase in mean grain size. Mid-tide samples range in mean 

 grain size from 0.25 to 2.5 phi, with an average mean of 1.25 phi. Beach sands of Atlantic 

 Central Florida are judged to be from coastal erosion of the shoreface, onshore transport of 

 materials from adjacent shoal regions, and southerly longshore transport of materials into 

 the area. Contribution to the beach from the shelf is evidenced by the marked petrologic 

 similarities of the deposits, in particular the presence of a small percentage of oolitic grains 

 derived exclusively from the immediate shelf. Quantity and content of biogenic fractions 

 and the large mean grain size of both total samples and insoluble fractions, relative to 

 updrift beaches, indicate that coastal erosion and retreat have been more important in the 

 genesis of modern areal beach sands than southerly longshore drift. 



Texture and composition of the sand vary throughout the grid, but nearly all Type A 

 sand is suitable for beach restoration and the thick deposits associated with topographic 

 highs are the most suitable. Extensive sand deposits suitable as a borrow source comprise 

 The Bull (minimum volume 32 X 10* cubic yard), Ohio-Hetzel Shoal (minimum volume 

 76 X 10* cubic yard), and Chester Shoal (minimum volume 9 X 10* cubic yard.) 

 Calculations of suitable sand volume on the shore-connected shoals (Southeast, Chester) 

 were made only for areas where data coverage was considered dense enough for reliable 

 interpretation. Based on core samples and seismic data from other parts of shoals, and 

 extrapolation to unsurveyed shoal areas, such as the small shoals trending northeast of 

 Chester Shoal, the volume of suitable sand may be an order of magnitude greater than 

 calculated. 



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