50 NEW YORK STATE MUSEUM 



together with the fact that this abrupt change in slope occurs 

 in homogeneous syenite and away from any possible stream action, 

 makes the presence of a fault here quite certain. 



The eastern face of Little mountain is also very steep, much 

 more so in fact than the contour lines indicate, and the general 

 topographic and structural relations here also strongly suggest 

 faulting. Some signs of shearing were noted. The northward 

 extension of this fracture (dotted on the map) is more doubtful 

 though the topography, not well shown on the map, points to minor 

 faulting there. The strike of these two last named faults is almost 

 exactly at right angles to the other larger faults of the group.' 



Moose-No. 9 mountain faults. The Moose mountain fault, as 

 shown on the map south of Thurman village, is really only the 

 northern end of a very prominent fault which has formed the 

 steep escarpment along the eastern side of Moose mountain (Lu- 

 zerne sheet). 



No. 9 mountain fault strikes due north and south and has caused 

 the steep western front of the mountain. Some evidence of shear- 

 ing was noted. The displacement appears to have been no less than 

 500 feet, and the eastward downtilt of the earth block is evident. 



Potter-Birch-Heath mountain faults. The Potter-Birch moun- 

 tain mass is a fine illustration of a fault block with steep western 

 front and gradual slope away from the scarp toward the east. On 

 the western side of Birch mountain there is a very distinct shear 

 zone along which the syenite has been badly crushed and made to 

 appear much like a biotite schist. The Grenville, mostly lime- 

 stone, dips at high angles eastward sharply against the syenite 

 along the fault. The very distinct curving in of the fault against 

 the syenite mass is here better shown than for any other fault of 

 the quadrangle. The steepest portion of the scarp is at Daggett 

 pond where an almost precipitous wall of syenite rises 555 feet 

 above the pond. Judging by the present topography, the displace- 

 ment of this fault ranges from 300 to 600 feet, being greatest at 

 Potter mountain. 



The Heath mountain mass is a good illustration of a small fault 

 block eastwardly downtilted. The displacement is no less than 

 300 or 400 feet. It is possible that this fault is really a continua- 

 tion of the Potter mountain fault, though it is more than likely 

 a separate fracture as shown on the map. 4f 



The small mountain of syenite lying just across the river from 

 Heath mountain is a still smaller fault block much like that of 

 Heath mountain. 



