Area J. Area J, approximately 9 kilometers east of area H and imme- 



diately offshore of North Shore Beach, is defined by seismic lines 16 and 28 

 and core 76, . and consists of an outwash shoal from the Harbor Hill Moraine. 

 The surface of the shoal is characterized by several northeast-oriented ridges 

 (Fig. 23) with relief up to 6 meters; seismic line 16 shows that the shoal is 

 highly stratified with forset strata. Core 76 on the nearshore part of the 

 deposit is composed of 1.7 meters of silty medium sand overlying 1.8 meters of 

 medium to very coarse sand and small pebbles. The calculated sand volume 

 within area J is 7 million cubic meters. 



k. Area K - Townshend Ledge. This area is located about 2.7 kilometers 

 south of the Connecticut coast and just east of the entrance navigation chan- 

 nel to New Haven (Fig. 24). Area K rises to within 5.5 meters of the water 

 surface; the base is in about 10.4 meters of water to the north and up to 15.2 

 meters to the south. It is bisected by seismic profile 115, and core 58A was 

 taken in -11.3 meters of water toward the western end. The seismic profile 

 shows bedrock to be fairly high in the area but the ledge itself exhibits 

 internal stratification. Core 58A shows that the strata consist of silty 

 medium sand for the upper 0.5 meter and clean medium to coarse sand for the 

 next 1.7 meter. Based on these data, the estimated volume of sand is 3 

 million cubic meters; however, this volume could actually be several times 

 larger if the total relief for the entire ledge were considered. 



Core 59 to the south of area K shows that gray, fine-grained modern sed- 

 iment blankets the adjacent bottom and covers large quantities of sand and 

 gravel that are probably contiguous with the sediments on Townshend Ledge. 

 Core 59 shows 0.9 meter of silt overlying 1.7 meters of brown, clean, medium 

 to coarse sand. 



1. Area L - Roanoke Point Shoal . Area L is about 8 kilometers east from 

 area J along the north shore of Long Island between the major headland shoals 

 at Herod Point and Roanoke Point (Fig. 23). The area comprises the shoreface 

 region beween the -6- and -18-meter contour and is transected by three seismic 

 profiles; however, core 75 provides the only information on the actual physi- 

 cal character of the sediments in the deposit. Like the other deposits along 

 the north shore of Long Island, area L is an outwash plain from the Harbor 

 Hill Moraine to the south, but the presence of large bed forms on the bottom 

 suggests that the surficial sediments are being actively modified by present- 

 day estuarine tidal currents. 



Core 75 was taken on the nearshore part of the deposit in 7 meters of 

 water and contains 3.9 meters of fairly homogeneous, clean, fine to medium 

 sand. The seismic profiles show that these sandy sediments are probably 

 contiguous through the entire deposit. Seismic profile 28 offshore of the 

 deposit shows that older fine-grained sediments are present from fixes 738 to 

 752, which probably represent glacial Lake Flushing lacustrine deposits. 



Based on core 75, a sand thickness of 3.8 meters was extrapolated over the 

 area to compute a total sand volume of 40 million cubic meters. 



m. Area M. Area M, an elongate deposit more than 10.8 kilometers long 

 and about 1.8 kilometers wide north of the town of Mattituck (Fig. 25), occu- 

 pies the shoreface between the -3- and -18-meter contours; the presence of 

 sand waves with relief up to 4.6 meters shows that the area is frequently 



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