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GINSBTTRG, LLOYD, STOCKMAN AND MCCALLUM 



[CHAP. 22 



Fig. 7. Grain size and constituent composition of the sediments arovmd Andros Island, 

 Bahamas. (Data from Thorp, 1936.) 



West side — 7 samples Reef tract — 11 samples 

 Weight % < \ mm 68 4 



Constituent composition of fraction > J mm 



Algae 5 30 



Mollusks 14 15 



Coral 12 



Foraminifera 23 26 



Pellets and aggregates 48 9 



B. Gulf of Batabano 



Daetwyler and Kidwell (1959, pp. 6-11) show a coincidence of high mollusk 

 and Foraminifera content with fine grain size along the shorehne of a large bay 

 on the southwest side of Cuba (Fig. 8). Although information on the circulation 

 of water in the Gulf of Batabano is not available, it seems likely that the 

 interior and shoreline parts of the bay have restricted circulation. 



The predominance of mollusks and Foraminifera in the fine sediments of 

 areas where the water circulation is restricted (lagoons) is quite common in 

 areas of carbonate sediments and in areas of terrigenous sediments as well 

 (Ladd, Hedgpeth and Post, 1957; Parker, 1959). The association is not unique 

 to the lagoonal environment but can also be found at depth on open shelves 

 (Shepard and Moore, 1955, p. 1502). However, distinct differences exist between 



