conclusions were made by McMaster and Ashraf (1973) from their studies of 

 buried drainage channels on the New England shelf east of Long Island. 

 The Flushing Bay channel E (Fig. 13) projects southeast, crosses the Long 

 Island coast at the west end of Long Beach, and continues its southeast 

 trend across the inner shelf. The lower part of Figure 14 shows channel E 

 cross section from reduced seismic profile line RR located about 5 miles 

 (8 kilometers) off the coast; the limited record penetration prohibits 

 knowing the exact channel depth but it probably exceeds -350 feet (-106.7 

 meters) MSL. The eastern channel wall is relatively steep and clearly 

 defined; the absence of any confining channel wall on the west indicates 

 that fluvial erosion was more pervasive there. Nearly the entire inner 

 New York Bight landward of the Coastal Plain cuesta (Fig, 13) exhibits 

 evidence that the Coastal Plain surface was eroded 100 to 300 feet (30.5 

 to 91.4 meters) below sea level and subsequently covered by Pleistocene 

 outwash sand and gravel. This same geologic condition is shown on the 

 seismic profile reduction (Fig. 7) located about 10 miles (16.1 kilometers) 

 offshore, close to the cuesta. 



Ground water studies by Swarzenski (1963) showed that channel F con- 

 sists of several adjacent channels separated by topographic highs of the 

 Cretaceous-age Magothy Formation. The relationship of these channels to 

 the subbottom geology is shown in the top part of Figure 15. The channel 

 underlying Little Neck Bay (Fig. 13) is about 1.5 miles (2.4 kilometers) 

 wide, 200 feet (61 meters) deep, and filled with Jameco Gravel, Gardiners 

 Clay, and Wisconsin-age moraine material. Swarzenski (1963) showed (Fig. 

 15) that three secondary channels in the Manh asset Bay area were about 

 160 feet (49 meters) deep and one-half mile (0.8 kilometer) wide. Because 

 of the proximity of the channels it is likely the channels coalesced far- 

 ther south and eroded the broad, low relief, 280-foot-deep (85.3 meters) 

 channel to the east (channel F in Fig. 14) . 



The 260-foot-deep (79.3 meters) channel G underlying Hempstead Harbor 

 (Fig. 13) was discussed by Swarzenski (1963) and is shown in cross sec- 

 tion in Figure 15. The southern projection of this channel underlies the 

 western end of Jones Beach and lies east of seismic line RR (Fig. 14) . 

 However, an inshore seismic line about 5 miles (8 kilometers) from shore 

 (Fig. 2) shows some acoustic signals at -275 feet (-84 meters) MSL which 

 may be the channel floor. 



The Huntington and Centerport channels H crossing northern Long Island 

 were discussed in a ground water paper by Lubke (1964). These channels 

 (cross-sectioned in Fig. 15), underlie the reentrant harbors in Huntington 

 Bay on the Long Island north shore. The Huntington buried channel, one 

 of the largest drainage channels underlying the Long Island terrain, is 

 a maximum of 3.3 miles (5.3 kilometers) wide, exhibits a symmetrical cross 

 section, and the thalweg extends to a depth of -475 feet (-144.8 meters) 

 MSL. The Centerport buried channel (Fig. 15) has an asymmetric shape and 

 is separated from the Huntington channel by a topographic high composed of 

 apparent Magothy strata. It is a minimum of 1.5 miles (2.4 kilometers) 

 wide and extends to -100 feet (-30.5 meters) MSL. The southward projection 

 of these two channels (Fig. 13) is based on seismic profile evidence of 



45 



