150 



GREEN MOUNTAINS IN MASSACHUSETTS. 



shown by the general <li]> of the thick quartz laminae when such lamina' 

 can be distinguished from cleavage foliation quartz laminae. Locality 207 

 furthermore shows that stratification foliation may be so completely oblit- 

 erated that cleavage foliation alone is determinable. 



Fig. 50.— Thin section of serieite-cMorite -Bcbist traversed 

 Goodell hollow, enlarged 2 diameters, showing the relation of the 

 have occurred ;ilnnj. r < leuva^r [dunes. From a ]ihuto,»raph. 



t to thequartz, In pi 



from locality 184, 

 the slide fractures 



CASE VII. 



On the southwest side of Bald mountain, locality 242, the schist is 

 traversed by two sets of foliations with different strikes The stratification 

 foliation, distinguished by its plications, and in part by the continuity of 

 the mineral constituents of the lamina?, strikes north 40° to 50° east, 

 and dips 60° southeast. The cleavage foliation strikes north, and dips 

 35° to 40° east. The correctness of this observation is corroborated 

 by one at locality 95, on the northern face of Bald mountain, about 

 4,000 feet nearly in the direction of the stratification strike as thus deter- 

 mined. There the stratification foliation is indicated by great sheets of 

 quartz striking north 45° east, and dipping about 75° southeast, corre- 

 sponding to the minute plications in the surrounding schist, which are 

 crossed by a cleavage foliation striking north 3° to 5° east, and dipping 55° 

 east. The probable correctness of both these observations is still further 

 increased by the trend of the central ridge of Grreylock, which, southeast of 



