Channel B, projecting southeast from the present Hudson estuaiy 

 through the Verrazano Narrows (between Brooklyn and Staten Island) and 

 onto the inner shelf, owes its origin to late Pleistocene glacial and 

 fluvial erosion by the Hudson River. According to Lovegreen (1974), 

 the channel at the Verrazano Narrows is about 1 mile wide and is cut to 

 a depth of -330 feet (-100.6 meters) MSL into Paleozoic bedrock. Worzel 

 and Drake (1959) studied subsurface data and found the base of the 

 Hudson Channel was at -725 feet (-221 meters) MSL at Tarrytown, New York. 

 Williams and Duane (1974) reported seismic profile evidence of a probable 

 extension of the same buried channel with a thalweg depth of -300 feet 

 (-91.4 meters) MSL underlying the topographically expressed Hudson Shelf 

 Channel about 8 miles (12.9 kilometers) east of Sandy Hook (Fig. 13) . 

 They ascribe its origin in late Pleistocene time to scour by isolated 

 ice lobes, rapid but massive erosion by glacial lake debouchment and 

 fluvial erosion by the melt water enlarged Hudson River. 



Buried channel C, east of the Hudson Channel (Fig. 13), underlies 

 Coney Island and was recognized on only one seismic profile of marginal 

 quality. Exact channel orientation is difficult to determine, but it is 

 apparently north-south; the channel floor is cut into Cretaceous strata 

 to a depth of at least -275 feet (-84 meters) MSL. Position and dimensions 

 indicate the channel may be an older course of the Hudson River. 



Presence of channel D (Fig. 13) has been determined from evidence con- 

 tained on subsurface ground water maps of Queens County, Long Island, com- 

 piled by Soren (1971). Channel D appears on the western part of Figure 14 

 as a broad depression, more than 2 miles (3.2 kilometers) wide, a maximum 

 depth of -250 feet (-76 meters) MSL, and cut into the Raritan Clay (Creta- 

 ceous age). The channel has been filled with Jameco Gravel and Gardiners 

 Clay. Projection of the channel southeast under Jamaica Bay and the east- 

 ern end of Rockaway Beach is based on evidence shown in Figure 3 where the 

 Coastal Plain surface slopes seaward under far Rockaway Beach more than 

 -200 feet (-61 meters) MSL. Projection of channel D northward indicates 

 it underlies the small reentrant estuary immediately west of Flushing Bay 

 on the Long Island north shore (Fig. 13). The superpositional relation- 

 ship of ancestral buried channels under reentrant estuaries seems charac- 

 teristic of most buried channels crossing central and western Long Island. 



Channel E (Fig. 13) , underlies Flushing Bay, and is described by Soren 

 (1971); the profile and cross section (Figs. 3 and 14) indicate it trends 

 southeast. Channel E (Fig. 14) is about 1.5 miles (2.4 kilometers) wide, 

 reaches a maximum depth of about -450 feet (-137 meters) MSL, and exhibits 

 a broad U-shaped cross section for the upper 175 feet (53.3 meters) and a 

 steeper incised cross section for the lower 275 feet (84 meters) . These 

 differences in channel shape suggest that the upper part was eroded by 

 Pleistocene glacial ice during glacial advance stages responsible for the 

 Harbor Hill and Ronkonkoma Moraines. Based on the presence of Jameco 

 Gravel on the bottom of the channel, Soren (1971) suggested the channel 

 was initially eroded by fluvial processes in Cretaceous or early Pleisto- 

 cene time and enlarged and deepened by ice scour during one or more phases 

 of Pleistocene glacial advance. These same observations and attendant^ 



43 



