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NEW YORK. STATE MUSEUM 



with reference to the Long Lake and Port Henry-EUzabethtown 

 quadrangles that the Precambric rocks show no good evidence of 

 having been more than moderately folded or tilted, and this ap- 

 pears to be true of the North Creek quadrangle as well. 



Locally, the limestone and accompanying pyroxene gneiss may be 

 intensely contorted or twisted, probably being due to the more 

 plastic character of the limestone when subjected to great pres- 

 sure. The pyroxenic bands are often pulled apart into small lens- 

 like masses as shown in plate ii and figure 9. Other fine cases 

 of contorted limestone may be seen at the river bridge near Thur- 

 man station (ofif the map) ; just north of the Ferry at the river's 

 edge (see plate 3); along the road i>4 miles southwest of Kelm 

 pond; and along the road a little east of north of County House 

 mountain. 



Figure 9 represents a sketch, drawn to scale, of a mass of lime- 

 stone on the south side of Crane mountain which has been con- 

 torted and forced for 20 feet across the foliation bands of the 

 associated hornblende-garnet gneiss. 



Scale: 



Feet. 



Fig. 9 Sketch showing a peculiar arrangenjent of Grenville rocks as 

 seen by the roadside on the south side of Crane mountain and three-fifths 

 of a mile from the summit of the mountain. The limestone has been con- 

 torted and forced across the foliation bands of the associated gneiss. The 

 black patches represent drawnout fragments of pyroxenic gneiss. 



SURFACE OF THE GREAT SYENITE-GRANITE INTRUSIVE MASS 



The very ancient Grenville strata Avere invaded by a vast mass 

 of molten syenite and granite which, in part, pushed aside or up- 

 ward or engulfed some of the Grenville and, in part, left patches 

 of greater or lesser extent practically intact. This has largely given 

 rise to the very decided '' patchwork " appearance of the geologic 

 map. 



t 



