average speed of 3 knots. Lee (1969) documented the western edge of the 

 Florida Current approximately 6,000 feet (2,000 meters) offshore at Boca 

 Raton, along the edge of the Continental Shelf, with north-flowing sur- 

 face currents between 0.6 and 1.5 knots. He measured comparable south- 

 flowing currents in the same area which were attributed to large eddies 

 produced by the Florida Current. Raymond (1972) suggested that the 

 western edge of the current can move as far landward as the 60-foot 

 (18.3 meters) depth contour. 



In an analysis of long-period sea level data. Hicks (1972) determined 

 a trend in relative sea level rise of approximately 0.007 foot (0.2 centi- 

 meter) per year at Miami Beach. Assuming an average beach slope of 1 on 

 10, this means that the shoreline position will retreat more than 1 foot 

 (0.3 meter) in 16 years, due to this factor alone. 



Visual observations of wind waves collected by shipboard observers 

 for the U.S. Naval Weather Service Command were summarized by Walton 

 (1973), and are shown in Figures 11 and 12. These data show that the 

 largest percentage of waves are from the east and are less than 4 feet 

 in height. 



5. Beach Material. 



The beach material at all three sites is medium to coarse, shelly 

 sand. Rusnak, Stockman, and Hoffman (1966) reported a variable but 

 systematic increase in shell content from Jacksonville south to Miami, 

 with a high of 89 percent near Boca Raton Inlet. They attributed 40 to 

 50 percent of the shell material to erosion of the Anastasia Formation 

 and the remainder to newly formed shells. In a study of beaches in the 

 vicinity of Cape Canaveral, Field and Duane (1974) found that grain size 

 increased with increasing shell content and attributed high shell content 

 to local injection by erosion of coquinoid limestone. 



Duane and Meisburger (1969) observed a transition zone in shelf topog- 

 raphy and sediments in the vicinity of Boca Raton. To the north, the 

 gently dipping shelf was found to be composed of an homogeneous fine- to 

 medium- grained, gray, quartzose sand. To the south, the shelf was de- 

 scribed as a series of two or three steplike linear flats separated by 

 low reef like ridges, with sediments composed of white to gray, calcareous 

 skeletal sand and gravel. The inner flat is relatively fine sand and 

 rock separating the shelf and nearshore zones of coarser and composition- 

 ally dissimilar materials. Duane and Meisburger (1969) concluded that, 

 south of Boca Raton, sand movement between the beach and shelf either in 

 a landward or seaward direction was improbable. Similarly, based on a 

 study of the shelf sediments, they concluded that little if any sediment 

 is transported into the shelf area from the north of Boca Raton to the 

 south. They attributed i,n situ production of sediment by reef organisms 

 as the primary source of shelf sediments south of Boca Raton. 



Raymond (19 72) described the shallow offshore terraces, reefs, and 

 sand deposits of Broward County, including the Hollywood site, and 



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