Cape Canaveral. Standard deviations range from about 0.5 phi to over 1.5 phi, whicli is 

 moderately well-sorted to poorly sorted in terms defined by Friedman (1962). In particular, 

 the good sorting distinguishes fine-grained type A sands from type F shoreface sands. 



Increases in standard deviations of some samples are due principally to anomalously high 

 shell content, wiiich adds a coarse mode to the sand; also, some silt content derived from 

 subjacent deposits adds a fine mode to the sand. 



Most type A deposits are light gray (10 yr. 7/1 by Munsell Color Code). Color variations 

 adjacent to and south of Cape Canaveral as noted by Field and Duane (1974) and 

 Meisburger and Duane (1971) are generally absent because of the lack of variegated 

 carbonate grains, and the general overall fine grain size of quartz in which iron staining may 

 be more rare than in medium and coarse sands. Color of quartz sands in this region has been 

 examined by Judd, Smith, and PUkey (1969) who found that less than 40 percent of 

 medium and coarse quartz grains are iron stained. Surface and subsurface samples identified 

 as type A sediment show Uttle or no iron staining, in contrast to anomalous high staining 

 values for the coarser sands at Cape Canaveral (Field and Duane, 1974). Previous shelf 

 workers have identified iron staining as an indication of a relict history. However, recent 

 studies by Swift and Boehmer (1972) suggest staining may occur in the active submarine 

 environment and is dependent on mean grain size, with medium and coarser sands becoming 

 stained and fine sands remaining free of iron stain. 



Detrital quartz is the chief constituent of type A sands, normally accounting for 80 to 90 

 percent of the total grains. Other constituents include accessory detrital hght and heavy 

 minerals and biogenic carbonate grains. The fine and medium quartz grains are clear and 

 subangular to subrounded; internal discoloration and inclusions are rare. Surface textures of 

 coarse and very coarse sand grains are occasionally well rounded, probably as a result of 

 solution. Electron micrographs of grains from both the inner and outer shelf show solution 

 features to be more common in the Florida shelf sands than elsewhere on the Atlantic shelf 

 (Blackwelder and Pilkey, 1972). This may indicate a secondary or residual origin of the 

 grains from local quartzose sources. Other detrital minerals in type A sands are feldspar, 

 mica, phosphorite, and accessory heavy minerals. Field and Pilkey (1969) and Milliman 

 (1972) have reported the feldspar content of north Florida surficial deposits to average 

 about 1.5 percent and range from 0.5 to 4 percent with values increasing gradually from 

 Jacksonville towards Georgia. Mica flakes occur sporadically in trace quantities in north 

 Florida type A sands, whereas in central Florida they are absent (Field and Duane, 1974). 

 Phosphorite is a common constituent of sands in the survey area and has previously been 

 reported by Gorsline (1963) and MiUiman (1972), and on the Georgia shelf by Pevear and 

 Pilkey (1966). In type A sands phosphorite grains are black, brown and amber, and range 

 from silt to gravel size; their high luster and high degree of rounding indicate softness and 

 transport history. Individual samples having a high phosphorite content occasionally contain 

 fish and shark teeth. 



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