CHAPTER IX. 



CLAY DEPOSITS IN SYSTEMS OLDER 

 THAN THE CRETACEOUS. 



CONTENTS. 



Triassic. 



Devonian. 



Silurian. 



Cambrian and Ordovician. 



Pre-Cambrian. 



TRIASSIC. 



The Triassic or Newark series in, New Jersey consists chiefly 

 of red shales and sandstones with some masses of trap rock. It 

 has been described in detail in the Annual Reports of the State 

 Geologist for 1896 and 1897. It forms a belt across the State be- 

 tween the Highlands on the northwest and the Cretaceous strata 

 on the southeast, extending from the New York State line be- 

 tween Suffern and the Hudson river, to the Delaware river be- 

 tween Trenton and Holland. The red shale where disintegrated 

 forms a sandy, clayey soil of: shallow depth. Locally this may ac- 

 cumulate in hollows as the result of wash from surrounding slopes 

 and form clay beds of no great depth and limited extent, but so 

 far as known beds of this description are nowhere used. The 

 shale itself is for the most part rather gritty and not favorable for 

 use in clay products, but locally it is fine grained and suitable for 

 brick. It is so utilized at Kingsland, Bergen county, with ap- 

 parent success. A few experiments on shale from other localities 

 were made in the course of these studies, and although unfavor- 

 able and decisive so far as they went, they were not sufficiently 

 numerous to test the formation thoroughly. Beds suitable for 



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