island or, a theory which better fits the contours of the bottom of the Sound, the north fluke 

 may have been non-existent and Sound river may have passed into what is now Peconic bay and 

 out near the site of the present Shinnecock canal. The lesser drainage was not far different from 

 that now existing except in so far as that has been modified by glacial action. It is improbable 

 the Peconic valley existed at all. 



Having determined as well as possible what the shape of the Cretaceous surface was, the 

 next step was to draw the contours on the top of the Jameco fill and its overlying Gardiners 

 clay. 



The rock contours were assumed as those already determined by the U. S. Geological Survey 

 and shown in GW-13. These were, however, extended to cover the sound and the entire area of 

 the island although such extensions are decidedly problematical, they being determined in large 

 measure by the present Connecticut shoreline, three deep wells in Suffolk county and assump- 

 tions as to the general shape and slope in those sections where there is no information. 



It is then assumed that the Lloyd rested on or near the rock and contours were drawn, 

 filling in the missing gaps by assuming the thickness of the Lloyd strata. The Raritan clay sur- 

 face was then interpolated between the top of the Lloyd and the ceiling fixed by the deeper 

 Magothy wells. 



As there ie. very little information with regard to anything but the glacial deposits in Suf- 

 folk county, west of the hills south of Huntington, reliance was placed on drawing meridian 

 sections and trying to determine from the glacial wells the probable ceiling of the top of the 

 Magothy. This is far from satisfactory and all the contours in eastern Suffolk must be con- 

 sidered as purely tentative. 



170 



