B88g Glociofluviol Outwosh Heads 

 -4i«io' MM Norvnolk Moroine r 



. ^ Norwolk 



Figure 11. The Norwalk Islands of Connecticut are remnants of a late Wisconsin moraine 

 extending discontinuously from Queens County, Long Island, northeast to the 

 New Haven area. The lordship and Milford outwash deltas associated with that 

 moraine and the positive relief features at Cable and Anchor Reef, Eatons 

 Neck, Stratford Shoal, and Crane Neck also appear to have a glacial origin. 



c. Cretaceous and Paleozoic Bedrock . The acoustic reflector marking the 

 top of the bedrock is the strongest and most continuous of any on the records 

 (Fig. 12). Except in deep channel areas such as off New Haven, in central 

 parts of the Sound, and along much of the north shore of Long Island, the 

 bedrock is present on the records. However, it is difficult to differentiate 

 Cretaceous strata from underlying Paleozoic rock because of limited resolution 

 on some profiles and lack of penetration into the Cretaceous strata. The 

 exact northern limits of the Cretaceous cuesta are difficult to determine, but 

 they appear to be close to the north shore of Long Island in the east and 

 strike west through the center of the Sound in the vicinity of Stratford Shoal 

 and then underlie the northern neck areas of western Long Island. 



The surface character of the bedrock is of extremely high relief, and 

 contour patterns are difficult and at times impossible to identify in certain 

 areas because of the extent of massive downcutting and widening of then exist- 

 ing channels by the glaciers and melt water. In the western Sound, several 

 large channels are present on both the Connecticut and Long Island sides 

 and all appear to deepen toward the center of the Sound. Williams (1976) 

 described six channels with thalwegs reaching -61 to -145 meters that under- 

 lie the recessed bays of northwestern Long Island and apparently transect the 



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