(6) Area A-6. A large irregular shoal centered 5 to 6 nautical miles offshore between 

 Jacksonville Beach and St. Augustine is judged to be the best prospect in the northern part 

 of the study area. In general, the shoal is of very low rehef and nearly flat -topped. 

 Geophysical records indicate the shoal may have formed by accretion, possibly during the 

 latter part of the last transgression. If so, this is an exception as most similar shoals off north 

 Florida appear to be erosional remnants. The few cores from the highest part of the shoal 

 recovered up to 10 feet of clean uniform quartz sand of medium and coarse size. Two small 

 ridge-like features surmounting the shoal and its highest central part are considered the best 

 prospects. If this shoal was formed entirely by accretion, the total volume of sand within 

 the shoal would be approximately 178 X 10* cubic yards. However, the typical bank 

 shoals appear to be largely products of erosion. 



(7) Area A-7. This is the only prospective site within the St. Augustine grid. Two 

 cores penetrated a clean medium quartz sand layer 4 to 6 feet thick. A ridge -Uke feature 

 near core 123 is judged to be the most likely locale for a suitable borrow area. The 

 estimated volume of sand in this ridge is 7.4 X 10* cubic yards. 



(8) Area B-1. Core 2 off St. Marys River Entrance at Fernandina contains 5 feet of 

 clean well-sorted fine sand with an average mean diameter of 0.218 milUmeters (2.2 phi). 

 The core is 5 feet long and terminates in sand; total depth of the deposit is unknown. The 

 deposit is apparently not extensive as surrounding cores do not contain similar material. The 

 material in this deposit may be related to the nearby inlet. 



(9) Area B-2. This area, of unknown extent and depth, is centered on core 11 south 

 of St. Marys River Entrance. The core is 5 feet long and consists of well-sorted, quartz sand 

 of fine to medium size. Core 11 is the shallowest core taken in the Fernandina area (—20 

 feet MLW) and thus represents an upper shoreface locale which was not sampled elsewhere. 

 The sand deposit may therefore extend laterally along the upper shoreface, but is unUkely 

 to extend any appreciable distance seaward since all cores in the zone immediately seaward 

 of this locale contain fine silty sand. 



(10) Areas B-3, B-4, and B-5. Three low, roughly Unear shoals lying parallel to shore 

 off Ameha Island may contain thick sand accumulations. No core data are available for these 

 areas; however, if they are composed of the fine silty sand typical of the inshore zone it 

 would not be well suited for beach fill. 



Since these shoals are close to shore and would be desirable borrow sites if suitable 

 material were available, they warrant further investigation. 



(11) Areas B-6 and B-7. Both of these areas consist of small shoreface-connected 

 linear shoals in the vicinity of Nassau Sound. Elsewhere, most similar shoals have been 

 found to be composed of clean sand. Since there are no cores from these shoals the 

 character and size gradation of the shoal sediment are unknown. Proximity to potential 

 project sites would make these areas desirable borrow sites should they contain suitable 

 material. 



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