Sediment Type III (fine to medium sand) is the most predominant facies in the study 

 area. (See Figure 14.) It mantles much of the sea floor from the shore out to about the 

 80-foot depth contour and appears in most samples to be moderately well- to well-sorted 

 quartzose sand. (See Figures 15 and 16.) 



Sediment Type IV is very fine sand and silt (Fig. 17) found in four general areas. (See 

 Figure 14.) The area at the head of the Hudson Channel fringes the seaward edge of the 

 medium sand and possibly represents the finer sediment winnowed out and carried by 

 seasonal bottom currents toward the channel. Some of the fine detritus is disposal material 

 as evidenced by intermittent occurrence of glass shards and coal fragments in the cores. (See 

 Figure 13.) The large area southeast of the study area is mantled by clean, well-sorted, very 

 fine sand to a depth of 15 feet, as evidenced by cores 87, 88, and 89. (See Figures 2 and 

 14.) The ellipsoidal area about 1.5 miles south of Rockaway Beach is defined by five cores 

 (averaging about 6 feet in length) which show that very fine sand overlies a moderately 

 well-sorted fine to medium sand. The patch of Type IV sediment in Raritan Bay, as shown 

 in core 4, rests on top of medium size reddish brown sand and probably results from recent 

 reworking of underlying relict fluvial sands and deposition of estuarine sediments. 



Sediment Type V is silt and mud characterized by high percentages of mica. (See 

 Figure 17.) Distribution is restricted to parts of the Hudson (submarine) Channel and to the 

 disposal areas for sewer sludge and dredge spoil; both are proximal to the head of the 

 Hudson Channel. (See Figure 14.) The mineralology and sedimentary character suggests that 

 sediment Type V is a Pleistocene estuarine facies or represents Coastal Plain facies exposed 

 by erosive downcutting by the Hudson River during Pleistocene lower sea stands. The first 

 contention that sediment Type V is older channel fill which has subsequently been cut by a 

 more recent Hudson drainage channel is supported by Figure 18. It is likely that farther out 

 on the shelf Coastal Plain strata crop out in the channel. 



IV. SEDIMENT ORIGINS 



A number of investigators have attempted to deciper the origins of Atlantic Continental 

 Shelf sediments. (Colony, 1932), (Alexander, 1934), (McMaster, 1954), (Schlee, 1968), 

 (Ross, 1970), (Schlee and Pratt, 1970), and (Milliman, Pilkey and Ross, 1972.) Several 

 authors recognize the influence glacially derived material has had on total sediment 

 composition of the shelf south of the Long Island terminal moraines (Alexander, 1934; 

 McKinney and Friedman, 1970), but little is known in detail about sediment composition in 

 the inner bight and the role the Hudson River played in influencing sediment distributions. 



The results of analyses of sediment from the tops of 24 cores taken in the inner bight are 

 shown in Figure 19. Analyses included mineral composition and relative abundance, grain 

 textures and color. To eliminate any significant results which may be attributed to grain size 

 variation only sediment in the 0.125 to 0.250 millimeter (2.0 to 3.0 phi) range were used. 



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