(2.3 meters) o£ medium to coarse sand overlying 4.5 feet (1.4 meters) of 

 organic mud which in turn overlies clean fine sand to the bottom of the 

 core at 13 feet (4 meters). Based on these core data, the sand thickness 

 is judged to be between 2 and 2,5 yards (1.8 and 2.3 meters). 



f. Area F . Area F extends along the south shore of eastern Long 

 Island from Mont auk Point to Napeague Harbor and offshore from about 

 3.5 miles (5.6 kilometers) to the limits of data coverage (Fig. 27). 

 The area contains 14 cores which are fairly evenly distributed, and all 

 except core 23 exhibit suitable sand for their entire lengths. Based on 

 core data, the minimum sand thickness is judged to be 3 yards (2.7 meters) 

 and the potential thickness is thought to be 5 yards (4.6 meters). The 

 seismic records show the sea floor in the eastern quarter is covered by 

 large amplitude sand waves and the central part includes a lobate delta- 

 like positive feature defined by the 60-foot (18.3 meters) depth contour; 

 both of these features are especially promising. However, the seismic 

 records show possible sand thicknesses of 13 yards (11.9 meters); true 

 determinations cannot be made without aid of deeper cores. Also, it must 

 be emphasized again that the seaward boundaries for all the borrow areas 

 along the Long Island coast are only approximate and the indicated bound- 

 aries extend seaward only to the limits of data coverage. In all poten- 

 tial borrow areas the seismic records indicate that the sand lithologies 

 continue seaward beyond data coverage. 



g. Area G. This area is more narrow than other borrow sites and con- 

 tains cores 29, 30, and 119 in the actual borrow area and cores 120 and 

 121 on the seaward side (Fig. 27). Cores 120 and 121 contain unsuitable 

 silty, very fine to fine sand. The three cores within the borrow area 

 contain clean sand for their total lengths; seismic records support a 

 minimum thickness of 4 yards (3.7 meters) and a potential thickness of 

 4.3 yards (3.9 meters). 



h. Area H. This area is rectangular in shape with a flat and gently 

 seaward-sloping sea floor to the 90-foot (27.4 meters) depth contour (Fig. 

 27). It contains five cores (31 through 34, and 118) all of which have 

 clean sand for their entire lengths. The minimum surficial sand cover is 

 3 yards with a reasonable potential of 4.3 yards. 



i. Area I. A trapezoidal-shaped region immediately east of Moriches 

 Inlet (Fig. 27), area I owes its shape to a southward extension of data 

 along seismic line 51 (Fig. 2). The five cores (35, 36, 115, 116, and 

 117) in this area penetrated a minimum of 9 feet (2.7 meters) at core 36, 

 and a maximum of 19 feet (5.8 meters) at core 116; all five cores showed 

 continuous sand sequences for their entire lengths. Based on these values 

 the minimum sand thickness is 4 yards and the potential thickness is 5 

 yards. Presence of shoal (ridge and swale) topography in the southern 

 part of the area may have considerable influence on sand availability 

 because data from other geographic shelf areas indicate that shoals may 

 be important sand repositories (Duane, et al., 1972; Williams and Duane, 

 1972). The western boundary for area I was established because core 79, 

 seaward of Moriches Inlet, contains gray, very fine sand silt overlying 



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