ORIGIN AND CLASSIFICATION OF THE 

 GREENSANDS OF NEW JERSEY.^ 



CONTENTS. 



Introduction. 



General Stratigraphical Features. 



Description of the Formations. 



Matawan Formation. 



Navesink Formation. 



Redbank Formation. 



Rancocas Formation. 



Manasquan Formation. 



Shark River Formation. 

 Origin of Greensand. 

 Genesis of the Deposits. 

 Source of the Materials. 

 Taxonomy. 

 General Conclusions. 



INTRODUCTION, 



During the past two years the writer has been carrying on 

 investigations upon the Cretaceous and Tertiary formations of 

 New Jersey under the joint auspices of the State and National 

 Geological Surveys. A preliminary study of the whole area 

 was followed by the mapping, with the aid of others,^ of three 

 United States Geological Survey atlas sheets in the northern 

 portion of the district, and more recently by the critical exam- 

 ination of five type sections across the state. The results of 

 the earlier investigations have just been published, 3 while the 

 later work will appear in the next annual report of the State 

 Geologist. 



In an area which had received such full investigation by as 

 competent a geologist as the late Professor Geo. H. Cook, for 



' Read before the Geological Society of America, at Boston, December, 1893. 

 = The writer had associated with him as assistants Messrs. C. W. Coman, H. S. 

 Gane and R. M. Bagg. 



3Rept. of the State Geologist of N. J. for 1892, pp. 167-246. 



161 



