GEOLOGICAL SECTION OF NEW JERSEY 275 
GLACIAL DEPOSITS 
Kansan or pre-Kansan drift—Glacial drift, both stratified or 
unstratified, greatly antedating the moraines of the Wisconsin epoch, 
occurs more or less discontinuously south of the Wisconsin moraine, 
to a maximum distance of 23 or 24 miles. In the Highland belt it is 
thicker and more continuous in the wider valleys than on the ridges, 
while on the Triassic piedmont plain it caps isolated and more or 
less flat-topped hills in relations which indicate prolonged erosion, 
since its deposition. The great age of this drift is indicated by the 
fact that the main streams have sunk their channels too feet and have 
opened wide valleys on extremely gentle gradients since it was formed. 
Its complete oxidation and leaching and the disintegration in situ 
of even large bowlders of gneiss and granite deep within its mass 
are other evidences of its great age. It is believed to be at least as 
old as the Kansan drift and may be even older. 
Wisconsin drift—A great terminal moraine of the Wisconsin 
ice-sheet crosses the state from Perth Amboy to Belvidere. Narrow 
valley trains of glacial gravels characterize some of the southward 
drainage lines, notably Delaware Valley, and locally overwash 
plains are conspicuous topographic features. North of the moraine 
the rock surface is covered by the usual assemblage of drift deposits, 
stratified and unstratified. At least two definite halts in the ice 
retreat are marked by recessional moraines and valley trains which 
head in them. The warped shorelines of an extinct glacial lake in 
the upper Passaic Valley indicate a differential elevation of the north- 
ern part of the state of about 2 feet per mile, since the retreat of the 
Wisconsin ice-sheet. 
NON-GLACIAL DEPOSITS 
The non-glacial Pleistocene deposits consist of gravels, sands, and 
some clays,’chiefly of fluviatile origin, but deposited partly at least in 
connection with estuarine conditions. Three formations have been 
differentiated, the Bridgeton, Pensauken, and Cape May, partly on 
lithologic and partly on topographic grounds. Each of these repre- 
sents a period in which both erosion and deposition occurred in this 
region but in which deposition predominated. They were separated 
by intervals in which on the contrary erosion prevailed over deposition, 
