758 KEW YOEK STATE MUSEUM 



Feet 



Black marble one or two in. beds • 13 



Black, massive, fine grained limestone. In floor of quarry 8 



Dark gray, fine grained limestone 25 



Black, compact limestones with slaty layers. ' \ 



It overlies the Chazy. There are also extensive outcrops of it 

 around Hoosick Falls, but at this point the stone is apt to be 

 slaty. 



The Trenton rocks also extend northward from the Mohawk 

 valley to Watertown. They are quarried at Prospect, Oneida, 

 Port Leyden, Boonville and Watertown. The Trenton limestone 

 formation is dark gray to black and is often fossiliferous. The 

 central part of the Trenton formation is apt to be shaly in places, 

 while the Birdseye limestone is massive and heavy bedded. The 

 upper part of the Trenton formation or Trenton limestone proper 

 is a lighter gray limestone and finely crystalline in its nature. 

 This member is quarried at Prospect. 



Niagara 



In Schoharie county we find the eastern end of this formation. 

 Its thickness is not more than 5 feet, and it is usually a dark gray, 

 massive limestone. An exposure of it can be seen at Howe Cave 

 just below the cement quarries, of which it forms the floor. 



The Niagara limestone also appears in Oneida county north of 

 C'layville and extends westward with increasing width to the 

 Magara river. In Wayne county in the town of Butler^ it is 

 a dark blue, fine grained, compact limestone and is usually thin 

 bedded. It has been used at this point for burning lime. Other 

 occurrences are at Pose on the head waters of Sheldon creek 

 and in the towns of Marion and Walworth. It has been quarried 

 at many points in Wayne county for the manufacture of lime. 



In Monroe county the northern edge of the limestone passes 

 through the towns of Penfield, Brighton, Gates, Ogden and 



^ Darton, N. H. Helderberg limestones and associated formations in 

 eastern New York, (see 13th an. rep't N. Y. state geol. p. 318) 

 2 Hall, James. Geol. 4th dist. N. Y. p. 84. 



