seismic profiles to map the bedrock configuration of the ancestrial Quinnipiac 

 River valley that underlies New Haven Harbor to depths of -224 meters and is 

 about 2 kilometers wide. It is the deepest of any of the river valleys enter- 

 ing the Sound and apparently follows Triassic faults and projects southwest 

 into the Sound. Sanders (1965) described one boring that showed the upper 35 

 meters of fill sediment is sand and gravel outwash with frequent occurrences 

 of estuarine organic mud. 



Presence of varved lacustrine deposits in coastal areas adjacent to the 

 Sound led several investigators (Antevs, 1928; Frankel and Thomas, 1966; 

 Bertoni, Dowling, and Frankel, 1977) to surmise that one or more large 

 freshwater lakes occupied the Sound during the Pleistocene epoch. Upson and 

 Spencer (1964) and Williams (1976) show that these deposits also fill many of 

 the deeply eroded river channels that were connected to the Sound when sea 

 level was below present levels. 



Akpati (1970; 1974) reported results of a study on the surfacial sediments 

 and foraminiferal ecology of eastern Long Island Sound to Fishers Island 

 Sound. He examined grain textural properties and mineral compositions at 53 

 sites, including 3 of the CERC cores included in this report. Donohue and 

 Tucker (1970) reported on marine minerals in Connecticut waters based on a 

 program of coring at 8-kilometer grid spacing and using low-power acoustic 

 profiling and bottom photography. They were able to identify some deposits of 

 sand and gravel and certain heavy mineral concentrations, but the results 

 appear to be of limited value for resource evaluation. The Pleistocene and 

 Holocene history of the western Long Island region was studied in detail by 

 Newman (1966); he reported evidence that a large glacial lake occupied the 

 Sound region before the last ice advance, and that the sea began filling the 

 Sound subsequent to about 12,000 years before present (B.P.). 



In 1970, the New York Ocean Science Laboratory started a study in eastern 

 Long Island Sound to determine residual drift patterns of the surface and 

 bottom waters. A preliminary report by Hollman and Sandberg (1972) showed 

 that the Sound was stratified with surface waterflow out of the Sound at an 

 average speed of 6 centimeters per second, and bottom waterflow into the Sound 

 at 1.2 centimeters per second. 



Grim, Drake, and Heirtzler (1970) summarized 10 years of seismic reflec- 

 tion and magnetic survey work on the subbottom character of the Sound. They 

 report that the Paleozoic bedrock and Cretaceous sedimentary rocks are highly 

 dissected and irregular with relief on the order of scores of meters and that 

 Pleistocene and Holocene sediments fill most of the relief surfaces to produce 

 the present rather shallow and even bottom. 



In eastern parts of Long Island Sound where it connects with Block Island 

 Sound, McMaster and Ashraf (1973a, 1973b), Coch (1974), and Williams (1976) 

 identified deeply buried stream channels which are pre-Pleistocene but acted 

 as conduits for glacial advances and melt-water streams. These studies are 

 germane to this study because many of the channels originated in Connecticut 

 and traversed the Sound, and the processes responsible for the subbottom 

 geologic character are similar throughout the entire southern New England 

 region. 



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