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which have been deeply eroded by Pleistocene glacial processes and covered by sand and gravel 

 outwash. South of Shrewsbury Rocks Coastal Plain strata have been evenly truncated and covered 

 by a veneer of residual material. Three primary types of bedding have been observed on the seismic 

 records. Coastal Plain strata exhibit a monoclinal regional southeast dip; steeply inclined crossbeds 

 are restricted to an elongate basin east of Sandy Hook, considered to be of fluvial origin. The third 

 type is Pleistocene-Holocene stratified fluvial sands and gravels which are regionally discontinuous 

 and exhibit gentle seaward dip. Cores reveal that fine to medium sand is the predominant sediment 

 type on the inner shelf. Isolated patches of coarse sand and rounded pea gravels are present off 

 Long Island where fluvial materials are exposed. Coarse sediment off New Jersey is judged to be 

 residual from sea floor outcrops of Coastal Plain strata. Very fine sand, silt and muds comprise the 

 sea floor at the head of the Hudson Channel and along the body. 



Sand suitable for beach nourishment projects is found in abundance throughout the shallow shelf 

 parts of the Inner New York Bight. Sea floor topography is fairly flat and sasid occurs as blanket 

 deposits. It is estimated that over 2 billion cubic yards of clean sand is available for retrieval by 

 present dredging techniques. 



Comparison of bathymetric maps made from 1845 to 1970 has confirmed that significant parts 

 of the natural Hudson Channel have been filled from ocean disposal of up to 1 billion cubic yards of 

 assorted anthropogenic materials, resulting from early construction in New York City and channel 

 dredging within the estuaries and bays. 



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