Cores 178 through 180 contain Type E material with characteristics similar to those in 

 the Cape Canaveral and Fort Pierce areas. However, the sediment included a number of large 

 shells (Mercenaria campechiensis) which are chalky white, highly bored and altered, and 

 contain large crystals of calcite indicative of subaerial exposure. 



Sediment contained in core 181, primarily a brown, medium quartz sand, is anomalous 

 compared to adjacent cored sands. (Figure 16.) The sand, about 80 percent quartz and 20 

 percent highly worn and bored pelecypod and barnacle fragments, is similar to those 

 described by Meisburger and Duane (1971) from the Fort Pierce region. There are many 

 similarities in sediment character of the Fort Pierce and Cape Canaveral shelfs, but distinct 

 differences in faunal and mineral assemblages. This stretch of the shelf is considered a 

 transition zone between the two areas. 

 3. Areal Beach Sediments. 



Areal beach sediments range in size from coarse to fine sand and contain between 2 

 percent and 58 percent acid soluble material. These variations in grain size and shell content 

 of beaches between Melbourne Beach on the south and Ponce de Leon Inlet on the north 

 are a result of coasthne orientation and exposure, availabiUty of offshore source materials, 

 and local Pleistocene coquina outcrops. Changes in sediment character are further induced 

 by intense periodic storms, tidal fluctuations, and seasonal changes in wave direction. 



Location, percent acid soluble material, mean grain size, and sorting are plotted in 

 Figure 17 for each of 28 beach samples. Each location represents a single sample collected 

 from the swash zone at a specific time; values shown in the figure are not fixed averages. 

 The results show the subtle regional trends and overall variation in characteristics of areal 

 beach sands. 



Curves for mean, sand size and shell content are directly related— nearly every increase in 

 shell content is paralleled by an increase in mean grain size. This pattern indicates that mean 

 sand size is primarily a function of composition, and is shown by the sorting curve. 

 (Figure 17.) The sorting curve does not always parallel the other two, but decreases in grain 

 size and shell content are frequently marked by a decrease in the standard deviation, 

 indicating better sorting. It further demonstrates the influence of shell material in the areal 

 beach sediments; sands containing lesser amounts of shell material are finer and appear to be 

 better sorted than those enriched in biogenic sand. 



Four distinct beach profiles along this coastal segment are shown in Fig. 17. Northern 

 beaches (New Smyrna, Daytona) have a low profile; those opposite Mosquito Lagoon and 

 south to Cape Canaveral are steeper. Beaches in the Canaveral Bight region (Cape Canaveral 

 to Canaveral Harbor) are low profile beaches periodically covered by large piles of shell 

 rubble. South of Canaveral Harbor, beaches have low and medium slopes but their profiles 

 are occasionally disrupted by Umestone outcrops. Northern low profile beaches are 

 composed of fine quartz sand (Sample CN 106, Fig. 18). New Smyrna Beach and 

 neighboring beaches are similar in morphology and composition to Daytona Beach on the 

 north side of Ponce de Leon Inlet, and probably represent accumulations of sand from that 

 region. The long stretch of steep beach near Mosquito Lagoon is undeveloped and almost 

 inaccessible; only a few samples were obtained and Uttle is known of the region. Of 

 particular interest is the increase in percent soluble material from 2 percent near Daytona 

 (Sample 012-106, Fig. 17) to over 30 percent opposite Mosquito Lagoon (Sample UM 12, 

 Fig. 17). The change is persistent; all other samples north of Cape Canaveral contain 20 to 

 50 percent carbonate. Examination of aerial photos of the area for coquina outcrops 

 revealed no surface exposures. These outcrops probably occur in the subtidal zone. The 



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