NE 



Area 'a' Shoals 





sw 



Line i f|il5 Walef Surface-^ 



/ \ C„ r ,3. 



Fli 10 



Molinicock Pi 





— ^L. »>»••> A™^-»»^_ 





- 



. ;«-- ' 



/^P^- 





==?» __ 



'- / / ^ ii "^ V 







- 



L— ~~~s 







-E 



E- 







_I 



Figure 18. Interpreted profile of seismic line 1 of two shoals off 

 Matinicock Point (see Fig. 17 for location). 



36, taken on the shoal in 14.3 meters of water, contains 0.9 meter of silty 

 medium and coarse sand overlying 3.4 meters of poorly sorted, very coarse sand 

 and gravel. These data support the calculation that 6 million cubic meters of 

 sand and gravel is available for area B. The disadvantages of this site are 

 its distance of more than 7 kilometers from the Connecticut shore in the 

 middle of the Sound, and its proximity to the dredged-material disposal area. 



c. Area C - Cable and Anchor Reef . This area is the largest of several 

 shoal features which trend in a north-south line from the Norwalk shore of 

 Connecticut to Eatons Neck Point on Long Island (Fig. 17). Cable and Anchor 

 Reef is in the middle of Long Island Sound surrounded by water depths of 21 to 

 34 meters, but it rises to within 6.7 meters of the water surface. Seismic 

 profile line 108 shows the shoal is composed of steeply dipping forset-type 

 sedimentary strata; core 7A taken in 17.7 meters of water in the northern end 

 contains 3.1 meters of medium to coarse sand and gravel. Using a conservative 

 thickness of 3.1 meters, the calculated sediment volume is 4 million cubic 

 meters. 



The disadvantages of using this site for extraction of sand and gravel 

 are the same as for area B to the west, except that two designated dredged- 

 material disposal areas are immediately west of area C and any dredging 

 activity would have to be coordinated with uses of the disposal areas. 



d. Area D - Eatons Neck Shoal . This site is part of a ridge extending 

 north from Eatons Neck, Long Island, and apparently has a common origin with 

 Cable and Anchor Reef (area C) to the north (Fig. 17). Both of these features 

 probably relate to glaciof luvial depositional processes during the Pleistocene 

 epoch. Area D is confined to water depths of 6 to 18 meters for practical 

 purposes but its boundaries probably extend to the north at the apex of the 

 -18-meter contour (Fig. 17). Seismic profile lines 5 and 6 show that the 

 shoal is composed of forset-type strata; cores 26, 26B, and 38 show a compo- 

 sition of fine to medium sand on the east and medium and coarse sand and 

 gravel in the west. These data were used to compute a volume of 7 million 

 cubic meters for available sand and gravel within area D. 



e. Area E. Area E is located almost 5.4 kilometers southeast of the 

 Norwalk Islands and 9 kilometers south of Sherwood Point, and is bisected by 

 the 18-meter depth contour (Fig. 19). As shown in Figure 20, the area is on 

 the distal end of a southward-projecting ridge characterized by high-angle 

 forset strata. The ridge has an average thickness of 6 meters and appears to 

 be closely underlain by bedrock. Core 9 was taken on the northern part of the 



41 



