46 



Report of the State Geologist. 



near tHe centre of its course, at a point about due east of Ephra- 

 tah, where the amount is 250 feet, and the Utica slate is seen 

 abutting against the crystalline rocks Souch of this point the 

 crystalline rocks dip beneath the Potsdam sandstone and Calcifer- 

 ous, the throw decreases gradually and the fault dies out in the 

 overlying Trenton limestones, a mile north of Stone Arabia. To 

 the northward the Trenton and Birdseye limestones, the Cal- 

 ciferous, the Potsdam, and the crystalliQC rocks are clearly ex- 

 posed, coming up in succession along the dip on the west side of 

 the fault. The continuation of the fault through the crystalline 

 area to the main fault is not clearly exposed and the amount of 

 throw appears to diminish in the interval. 



West of Gloversville the course of the ''^oses" fault gradually 

 curves around to northeast and near Mayfield its trend is nearly 

 due east. Then it turns to the northnortheast again and extends 

 up the Sacandaga valley. Along the fault scarp in this region a 

 high cliff and steep slopes of crystalline rocks are presented to 

 the eastward and southeastward rising high above the plain on 

 which Gloversville and Mayfield are located. 



Figure 8.— Sketch map of region north of Mayfield, and sections illustrating the relations of the 

 faults. Horizontal scale two miles to one inch. U. Utica slate. T. Trenton limestone. C. Calcifer- 

 ous. P. Potsdam sandstone. A. Crystalline rocks. F. Faults. 



