558 NEW YORK STATE MUSEUM 



is an eastern representative of part of the lower Trenton, It m 

 hoped that this end has been attained, at least in so far that the 

 necessity of assuming an inversion of the beds will not be con- 

 sidered as necessarily fatal to the above mentioned conclusion,, 

 which appears fully warranted by stratigraphic and paleonto- 

 logic evidence. This evidence, which we may be allowed to sura 

 up here to emphasize the multiformity of its character, consists 

 in the observation of four zones, the lowest of which is the Nor- 

 mans kill shale; the observed intercalation of a conglomerate bed 

 containing lower Trenton fossils; and the discovery that this 

 shale rests on lower Trenton limestone. 



CLASTIC DEVELOPMENT OF TRENTON IN HUDSON 



RIVER VALLEY 



It seems appropriate to state here certain inferences which 

 can be drawn from the principal conclusion of this paper, and 

 which seem either to militate against other well known facts of 

 the geology of New York or apparently are difficult of explana- 

 tion. 



There is first the shaly development of the mass of the Trenton 

 in contrast to its typical calcareous character a short distance to 

 the west; for the correlation of the Normans kill shales with part 

 of the lower Trenton, of the Watervliet beds with the middle 

 Trenton and the absence of limestone beds between this zone and 

 the Utica shale zone necessitate the assumption of the replacing 

 of the Trenton limestone principally by shales and sandstones. 

 This view harmonizes with the well-known fact of the elastic 

 dievelopment of the majority of the formations in the Appal- 

 achian region, to which the investigated territory, by the char- 

 acter of the disturbances and of those of the neighboring regions 

 belongs. This clastic character and the great thickness of the 

 mass of shales are both characteristic features of the Appalachian 

 region, and of themselves constitute evidence in support of the 

 structure indicated. 



