232 E. T. Long — Minor Faulting 



Major Structural Features. 



The Watkins Glen. — Catatonk folio deals with the 

 region south of a point called Esty 's Glen which is located 

 about four miles north of Ithaca. To the north of this 

 point little work has been done, but one would expect to 

 find a continuance of the large features as shown, by 

 E. M. Kindle, 1 to exist in the region to the south, including 

 not only south central New York but northern Pennsyl- 

 vania as well. This structure is considered by him to 

 be the northward dying out of the results of the Appa- 

 lachian Mountain making whose trend and characteristics 

 it shares. The sinuous axes of the broad low folds of the 

 Chemung and Portage of this area are given in a sketch 

 map on page one hundred of the folio, as well as on the 

 Areal Geology sheet. The average trend is slightly N-E 

 to S-W of a true east-west line and would imply pressure 

 from a direction S.SE resistance being encountered in a 

 N.NW direction. Eastward they swing to a more nearly 

 E-W course. Prom the south to the north end of Cayuga 

 Lake successively older rock are continuously met, the 

 general dip being to the south, though it is not constantly 

 so. The order of succession is : Portage at Ithaca and to 

 the north, until the Genesee appears in the bottom of the 

 cliffs about half a mile south of Esty's. Something over 

 a mile to the north of this the Tully emerges from the 

 Lake and though seldom over 20' thick, dominates the cliff 

 face of Cayuga Lake (see ^g. 2) with but one break at the 

 mouth of Salmon Cr., for a distance of 14 miles to the 

 north, after which for three more miles it makes falls 

 heading deep ravines in the Hamilton shale beneath. The 

 steepness and occasional great height of the cliffs of 

 Cayuga Lake are therefore all the more remarkable since 

 they are cut in the soft shale of the Hamilton for over half 

 of the 40 miles of its shore line. 



The quarry in the Tully limestone at Portland Pt. 

 seems to be located on the crest of the major anticline of 

 the whole Cayuga area at an elevation of 640'. Beds dip 

 away from this point to the south for a short distance at 

 the rate of 6°, but after % mile assume the usual dip of 

 about 1°. This continues with but slight variation to the 

 south end of the lake. To the north, the beds dip a little 



1 Watkins Glen-Catatonk folio 169, U. S. G. S., pp. 98-111. 



