of a nearby core. Core 182, also contains somewhat anomalous material in 

 the form of a shell gravel consisting almost entirely of well preserved 

 shells of Mulinia lateralis , some shells of Donax variabilis and quartz. 

 Whether this stratum is a facies of the material found in the adjacent 

 Core 181 is not known. 



Very little data is available on sediments in the reconnaissance 

 area southward from Fort Pierce grid to Palm Beach. Only two cores were 

 taken in this area - both near the southern border of the grid. Moe 

 (1963) reports a rolling sand and shell bottom in the area with coral rock 

 reefs at 30, 70, and 130 to 140 feet; the shallow reef is obscured by 

 sedimentation in many places. Material found blanketing the shelf at 

 Palm Beach and southward to Boca Raton consists of a fine, well sorted, 

 gray quartzose sand dissimilar to any sediment found in Fort Pierce grid 

 except perhaps Type D. A transitional zone between the typical Type A 

 surface sediment of Fort Pierce grid and the gray sand body at Miami 

 Beach must occur in the reconnaissance area. If the presence of Type A 

 sediment is indicated by shoals (as seems to be the case) , this sediment 

 type probably persists as far south as 27°05'N because shoals similar in 

 form to those found in the Fort Pierce grid occur here. 



42 



