﻿S6 



NEW YORK STATE MUSEUM 



UNCONFORMITY 



Group f Cambro-Ordovicic formations 



(22) Hudson River slates, shales, and A Especially prominent as 



sandstones (very thick) (Or- 

 dovicic) more than 2000 feet 



(23) Wappinger limestone (1000 feet) 



(in part Cambric and in part 

 Ordovicic) 



(24) Poughquag quartzite (600 feet) 



(Cambric) 



surface formations in 

 the Shawangunk 

 range, the Wallkill 

 valley, and the region 

 eastward and south- 

 ward to the High- 

 lands, on both sides 

 of the Hudson 



Group g Later crystallines (South of the Highlands) 

 (Uncertain age) 



(1) The Manhattan schist, a thor- 



oughly and coarsely crystalline 

 sediment of uncertain age — 

 generally supposed to be equiva- 

 lent to the Hudson River slates, 

 (Ordovicic) but here separated 

 without necessarily raising that 

 question because of their very 

 different physical and petro- 

 graphic character 



(2) Inwood limestone (or dolomite), 



a magnesian crystalline, lime- f 



(3) 



stone of uncertain age, generally 

 supposed to be the equivalent of 

 the Wappinger (Cambro-Ordo- 

 vicic), but here enumerated sep- 

 arately without necessarily rais- 

 ing that question because of 

 their very different lithologic 

 character and associates 

 Lowerre quartzite, an occasional 

 quartzite of uncertain relations 

 and very limited development 



Confined to the region 

 east of the Hudson 

 river and south of 

 the Highlands proper, 

 occupying the region 

 from the Highlands 

 to Long Island 



