HIGHLY FOLDED BETWEEN NON-FOLDED STRATA 

 AT TRENTON FALLS, N. Y. 



W. J. MILLER 

 Hamilton College, Clinton, N. Y. 



While engaged in field-work for the New York Geological Survey 

 during the summer of 1907, excellent examples of highly folded 

 between non-folded strata were observed at Trenton Falls, north of 

 Utica, New York.^ The phenomenon occurs in the classic Trenton 

 limestone at its type locality. Vanuxem^ and T. G. White^ are the 

 only ones who have described and attempted to explain the phenome- 

 non at Trenton Falls. 



Layers of highly folded and broken limestone included between 

 perfectly straight and undisturbed limestone layers are well exhibited 

 along the sides of the gorge at Trenton Falls. The impure limestone 

 layers of both the folded and the non-folded portions average only a 

 few inches in thickness and are separated by thin shale bands. The 

 folded beds lie at two distinct horizons within the limestone formation 

 which here shows a thickness of 270 feet. Prosser and Cummings^ 

 have made careful measurements of the thickness of the Trenton 

 limestone at this locality. According to them the base of the lower 

 folded zone lies 144 feet below the top of the Trenton. This con- 

 torted zone is about four or five feet thick and is visible only opposite 

 the top of the lower part of High Fall and in the upper end of the 

 gorge near Prospect village where the strata are highly inclined. It is 

 well shown in Fig. A, PI. Ill of White's article. Prosser and Cum- 

 mings do not definitely refer to the upper folded zone in their paper, 



1 Published by permission of Dr. J. M. Clarke, State Geologist of New York. 



2 Natural History 0} New York — Geology 0} the Third District, p. 53. 



3 "The Faunas of the Upper Ordovician Strata at Trenton Falls, Oneida Co., 

 N. Y.," Transactions 0} the N. Y. Academy of Sciences, Vol. XV, pp. 71-96. 



4 Prosser and Cummings, Sections and Thickness of the Lower Silurian Forma- 

 tions on West Canada Creek and in the Mohawk Valley, 15th Annual Report of the N. Y. 

 State Geologist, pp. 615-27. 



428 



