249 



A Study of the Collections from the Trenton 

 and Black River Formations of New York.* 



By H. N. Coryell. 



The Trenton limestone in general is a formation made up of thin bedded, 

 dark bluish gray, compact limestone separated by thin shaly layers, except 

 the upper 25 to 35 feet which consist of a coarse crystalline, thick bedded 

 limestone with thin shaly partings. This formation is everywhere very fos- 

 siliferous. 



The type locality for the Trenton limestone is in the southwest part of the 

 Remsen quadrangle, along West Canada creek, at Trenton Falls. A detailed 

 section of the formation shown here is given by Prosser and Cummings, who 

 have measured the entire thickness of 270 feet with great care. The upper 

 portion does not appear in the Trenton Falls section, yet the work of W. J. 

 Miller shows that there is only a few feet omitted, since the crystalline beds 

 are at no place more than 35 feet thick upon which rest the Canajoharie shale. 



The bottom of the Trenton formation is not shown in the Trenton Fall 

 gorge, still the dip of the strata and the presence of the Lowville limestone a 

 few miles to the southeast makes it seem very probable that the lowest beds 

 in the gorge are not far from the base of the Trenton formation. Thus allow- 

 ing for the necessary addition to the top and the bottom, the thickness of the 

 complete section is at least 280 to 300 feet. The measurements taken at 

 Rome and at the Globe Woolen Mills at Utica show a greater thickness of the 

 Trenton to the southward and southwestward. 



The formations during the early Paleozoic were deposited upon a sink- 

 ing ocean bottom. The coast line receded to the northward. Younger forma- 

 tions overlap the older ones everywhere along the cost line and lay upon the 

 precambrian rocks. The Trenton is 510 feet in the Globe Woolen Mills well 

 at Utica, 575 feet in the Chittenango well, and 435 feet (including the Low- 

 ville) in the well at Rome. In the vicinity of Trenton Falls it has a maximum 

 thickness of 300 feet. Along the Precambric boundary there are indications 

 that it is much less. ( Considering I he slope of < he Precambric floor and cliffer- 



*A summary of the literature is given by Prof. E. R. Cummings in the Bulletin of 

 the New York State Museum, No. 34, Vol. 7, May, 1900. 



