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NEW YORK STATE MUSEUM 



glen; 13 feet in the quarry at Willard; 11 feet with possibly one or 

 two layers at the top wanting in the old Johnson quarry i^ miles 

 north O'f Ovid; and 14 to 15 feet in the ravines east of Hayt 

 Corners. 



The lighter color and rugged character of the Tully as compared 

 with the soft dark shales above it, imake it a prominent feature in 

 the stratigraphy of the cliffs on the lake shore and in the adjacent 

 ravines. Its line of outcrops on these quadrangles is more than 30 

 miles long and the frequency and extent of the exposures make it 

 possible to ascertain its position in reference to the lake level with 

 a good degree of accuracy. At the head of the Kashong creek 

 ravine the top of the limestone is 713 feet A. T., with a northward 

 dip that is reversed a little farther south, as it is 560 feet A. T. in 

 a small quarry i]/^ miles north of Dresden, and has the same ele- 

 vation at the Cascade mills in the Keuka outlet gorge. At the 

 mouth of Bruce gully it is 550 feet A. T. rising southward to 600 

 feet A. T. at the top of the falls in that ravine, and westward to the 

 same elevation at Seneca mills a mile west of Cascade mills. In 

 the Perry point ravine it is 565 feet A. T. Thence southward for 

 4 miles it is covered by drift to a ravine half a mile north of Plum 

 point where it is 478 feet A. T. 



It sinks below lake level 444 feet A. T. on the north side of Plum 

 point, rises 5 feet above in a small arch half a mile farther south, 

 is covered by water for 60 rods, then rises to the bight of 45 feet 

 above the lake in an anticlinal that holds it above the water across 

 Severne point and to the north side of Miller point where with a 

 2 degree southward dip it finally disappears below the lake level. 



Its emergence on the east side is covered by drift, its southern 

 exposure being 50 rods from the lake and 50 feet above it in a 

 small ravine i mile south of Lodi Landing. A strong southward dip 

 carries it below the lake level between this ravine and a small g'ully 

 54 mile farther south at the mouth of which the black Genesee shale 

 is exposed. It appears at the mouth of Lodi glen 30 feet above the 

 lake rising continually up the ravine for 75 rods showing a north- 

 westward dip of about 100 feet per mile. 



It is prominently displayed in the cliffs and ravines north of Lodi 

 Landing as a slightly undulatory light gray band 40 to 60 feet above 

 the lake level for 3 miles, then sinks to partial submergence ^ of a 

 mile south of the dock at Willard. It is 150 feet higher in the 

 quarry on Simpson's creek V& mile northeast. Its next outcrop is 

 in the old Johnson quarry i^ miles north of Ovid at the summit 



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