PLEISTOCENE CLAYS. 1.25 



beneath Oradell, and is present just south of Old Hook. It is 

 not known north of this point in the valley of the Hackensack 

 itself, but it is said to occur north of Closter, at Norwood and 

 at Neuvy. At Neuvy the clay was formerly worked, and its 

 thickness is said to be 28 feet. The clay at this point is not 

 now accessible. 



"In the valley of Overpeck creek the clay is also present as 

 far north as Englewood, and probably beyond. 



"This laminated clay was deposited in standing water, which 

 was moderately quiet. Into the water, masses of ice carrying 

 bowlders were sometimes floated, as shown by the occasional 

 large, glaciated bowlders in the clay. 



"The clay is known to overlie till at many points, and its 

 deposition is therefore later than the occupancy of the region 

 by the ice. At the north the surface of the clay is some thirty 

 feet above sea level, while at Little Ferry its surface is about at 

 sea level. Its surface, therefore, declines slightly to the south. 



"The depth of the clay is one of its most remarkable features, 

 The following data on this point have been reported : 



"At Neuvy, surface elevation 20 to 30 feet, 28 feet of clay. 



"North of Closter. surface elevation about 40 feet, 10 feet of 

 clay. 



At Oradell, surface elevation about 30 feet, 185 feet of clay, 

 beneath 1 5 feet of sand. 1 



"At Hackensack numerous borings have tested the depth of 

 clay, which varies from a few feet at the more northerly brick- 

 yards to 85 feet at Mehrhof's lower yard, and at the g-as works. 



"West of Bogota, on the east side of the river, the clay is re- 

 ported to be 215 feet thick. These figures make it clear that the 

 surface of the rock east and north of Hackensack is far below 

 sea level, and that, if the drift were removed, or even that part 

 of it which lies above the till, a great bay would cover the Hack- 

 ensack meadows, and extend far to the north. A branch of the 

 bay would run up the valley of Overpeck creek, for the surface 

 of the rock at Englewood is known to' be locally as much as 60 



1 It is suspected that the boring here may have been in soft shale, not dis- 

 tinguished in the drilling from clay. 



