To the north and east of Long Island the Gardiners clay has been tentatively identified as 

 far away as Cape Cod, to the south a correlation has been suggested with the Cape May forma- 

 tion which is however largely sand and gravel. While the relation of these more distant beds to 

 the type locality is highly speculative there seems to be no reason to doubt that the Gardiners clay 

 on Long Island is a part of a more extensive formation. There is considerable doubt however that 

 it exists in the bays of the north shore and it certainly cannot be present there over very wide 

 areas. Over most of the central part of the island, it cannot have been deposited at all since this 

 area was above sea level at that time. Its distribution therefore in western Long Island is very 

 similar to that of the underlying Jameco gravel, that is it underlies much of Kings and Queens 

 Counties, where over wide areas the upper surface of the Cretaceous formation is well below 

 sea level, and extends along the southern part of Nassau and Suffolk Counties. Along the north 

 shore, it may or may not be present in the bays. In eastern Suffolk County, the Gardiners clay 

 appears to be widely distributed where the less easily recognized Jameco gravel has not been 

 found at all. 



The most recent work on Gardiners Island, at the type locality for the Gardiners clay, 

 shows that there at least the typical f ossiliferous dark clay is overlain by dark brown and red- 

 dish varved clays. These varved clays are not interglacial, but glacial in origin and must have 

 been deposited in fresh water at a time when the ice was in the immediate vicinity. The extent 

 of these varved clays, or their exact relation to the other formations on the Island, is not known, 

 but their presence even locally is an added complication, and the exact manner of their origin 

 is difficult to deduce. 



With the formation of the ice sheet which followed the Gardiners interglacial period, prob- 

 ably the ice which laid down the Montauk till, sea level must have fallen as water was removed 

 from the ocean to form the ice. With the fall in sea level the Gardiners clay would have been ex- 

 posed and further deposition prevented. In places it may well have been eroded, although there 

 is no evidence of this. 



As the ice advanced still farther south, the sea level would at first have dropped a little 

 more and would then have remained at about the same level, or even have risen slightly. This 

 failure of the sea level to drop as the ice front approached Long Island, and the possibility that 

 sea level may even have risen is due to the great weight of the ice, which actually compressed the 

 "solid land" beneath it as it advanced. A few hundred miles in from the edge of the ice it is 

 known that the land was forced down even more than the sea level was lowered by the removal 

 of water. At the outermost margin of the ice it is not known which effect predominated, but it 

 was probably that of the removal of the water for there is no evidence to show that the sea level 

 on Long Island was ever higher than it is now. It would be of considerable interest to know 

 what did happen to the sea level around Long Island during the Pleistocene for this would help 

 more than anything else to explain the complex history of this period. 



It seems safe to assume however that, at the time when the post-Gardiners ice sheet was 

 advancing across what is now Long Island, sea level in this area was below the level of Gardin- 

 ers time. Perhaps as this ice sheet advanced, but more probably as it retreated, the varved clays 

 above the Gardiners were laid down in fresh water lakes. The southern margin of the lakes were 

 formed by at least a low ridge of land on Long Island, possibly the terminal moraine of the ice 

 sheet. The northern margin of the lake was almost certainly the ice sheet itself. 



The varved clays are apparently overlain with soft fluffy silty sand, probably a part of the 

 Jacob sand, but the Gardiners clay, the varved clay and this sand are so folded and distorted on 

 Gardiners Island that their relations are not claar. This folding was due to pushing by one of 

 the ice sheets, possibly the Montauk sheet or possibly the sheet which deposited the Ronkon- 

 koma moraine. 



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