Table 2. Summary of main sediment types. 



Type Lithology Description 



A 



Fine quartz sand 



Widely distributed surficial fine sand; 

 brown to gray; uniform, well sorted; 

 biogenic calcium carbonate 5 to 10 per- 

 cent; phosphorite up to 2 percent. 



B 



Very fine to fine 

 quartz sand 



Extensive deposits mainly in Onslow Bay; 

 uniform, well sorted, angular; light 

 brownish gray; biogenic calcium carbonate 

 2 to 35 percent; abundant foraminifera 

 in places, phosphorite up to 2 percent. 



C 



Very fine to fine 

 muddy quartz sand 



Extensive deposits in Long Bay; well to 

 poorly sorted, angular; dark grayish 

 brown; biogenic calcium carbonate, 

 mostly foraminifera, more than 50 percent 

 in places, phosphorite up to 3 percent, 

 glauconite 2 to 30 percent. 



D 



Medium to coarse 

 quartz sand 



Patchy distribution throughout study 

 area; heterogeneous usually poorly 

 sorted light gray to light grayish brown; 

 shell fragments constitute up to 30 per- 

 cent ; phosphorite up to 2 percent . 



E 



Shelly quartz sand, 

 shell sand, and shell 

 hash 



Patchy distribution throughout study 

 area; heterogeneous, usually poorly 

 sorted; variegated or uniform brownish; 

 shells and shell fragments constitute 

 30 percent or more. 



F 



Dark-gray clay 



Patchy distribution, mostly in Long Bay; 

 typically soft, highly plastic; dark 

 gray with yellow mottling; usually con- 

 tains very little sand-size material. 



G 



Calcareous biogenic 

 sand, gravel, and rock 



Occurs mostly in ancient channels; 

 heterogeneous, poorly sorted, in various 

 states of consolidation; light gray to 

 gray, occasionally pale brown; usually 

 80 percent or more biogenic calcium 

 carbonate; occasional granules or pebbles 

 of phosphorite. 



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