Correlation of the formation in the Williamsburgh and Greenpoint sections has been 

 hampered by the presence of clays geologically younger than the Gardiners clay, and the 

 dissection of the Gardiners surface which in some places has left the formation as an outlier 

 surrounded and overlain by younger glacial deposits. 



The formation has a gentle slope southward and its upper surface ranges from 50 to 180 

 feet below sea level. Its normal thickness is about 50 feet, but in the northern parts of Kings 

 County, where the unit rests on bedrock, it is generally only about 10 feet thick. In the buried 

 valleys in the central part of the County it may in places have a thickness of nearly 100 feet. 



In some places the formation consists chiefly of sand and probably does not provide a 

 very tight seal over the underlying Jameco gravel. This enables recharge of the Jameco to 

 take place and also results locally in the occurrence of water table conditions in the Jameco 

 formation which normally is under artesian pressure. 



Gardiners clay — Queens County: The Gardiners is readily identified in the southern half 

 of the County, where it overlies the Jameco gravels. Near the central part of the County the 

 Gardiners clay overlaps the Jameco and rests directly on the Magothy ( ?) formation. In the 

 vicinity of Newtown Creek in the northwest part of the County, the Gardiners lies directly on 

 the Raritan clay member, or bedrock. The presence of younger clays in this area hampers 

 geologic correlation as it does in Kings County. In the northern embayments a depth criterion 

 alone is not enough to identify the clay since it is known that Upper Pleistocene valley fill 

 deposits extend in places to a depth of as much as 100 feet below sea level. 



The upper surface of the Gardiners, which has been considerably eroded in places, ranges 

 from 50 to 200 feet below sea level. Its thickness ranges from about 10 feet to 150 feet, the 

 latter representing an unusual thickness observed in a well located in a buried Pleistocene 

 valley in the southeastern part of Queens County. 



Gardiners clay — Nassau County: The Gardiners clay extends from southern Queens into 

 the southern part of Nassau County, appearing as a fringing deposit beneath the south shore 

 areas of Nassau County. It overlaps the Jameco and in its northernmost extension rests directly 

 on the Magothy ( ?) formation. 



The upper surface of the Gardiners clay dips gently to the south and ranges from about 

 40 to 100 feet below sea level. It ranges from about 20 feet to 60 feet in thickness. 



Gardiners clay — Suffolk County: Very little is known of the occurrence and distribution 

 of the Gardiners clay in Suffolk County. There are several reasons for this situation. Primarily, 

 there are broad areas in the County which are devoid of information. Secondly, certain clay 

 beds at the eastern end of the Island which were correlated as Gardiners clay by earlier 

 investigators have been folded by ice shove and pushed up above sea level so that their strati- 

 graphic relationship to the deep-lying Pleistocene clays in western Long Island is somewhat 

 obscure. Finally, the superposition of lithologically similar beds of different geologic age beneath 

 the south shore of the County has made a clear cut separation of the upper 200 feet of sediments 

 in that area very difficult. These beds consist in part of fossiliferous glauconitic clays that have 

 been classified by different investigators as Gardiners clay, as part of the Magothy (?) forma- 

 tion, and even as Tertiary beds. Both Veatch and Fuller (9) (15) considered that the 

 northern limit of the Tertiary formations lay to the south of Long Island. 



The age of these deposits apparently cannot be determined by a superficial examination 

 of well samples, but requires detailed micropaleontologic studies of samples from many wells. 



The available data suggests that the Gardiners clay probably underlies the entire south 

 shore of the County and extends inland in the eastern part of the County for an unknown 

 distance. At Brookhaven National Laboratory in the central part of the County where the 

 clay has been detected in some core samples from test wells. In the western part of the 



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