110 NEW YORK STATE MUSEUM 



could thus have been so conspicuously resolved into forces at widely 

 divergent angles. That it was in such a condition is indicated by 

 the fact that the quartz which was the last mineral to crystallize 

 almost wholly escaped crushing in the central zone and that it is 

 less crushed than the other minerals in the northwest zone. The 

 compressive forces did not, however, cease immediately after the 

 consolidation of at least part of the Diana mass, since within a wide 

 zone along the northwest all the minerals, quartz included, show 

 pulverization or granulation. The central zone and the Croghan 

 mass are not thus affected, and the explanation may be either that 

 the border band was the first to arrive at a state of complete con- 

 solidation or that the forces died out as they passed away from the 

 border toward the southeast. Since the dividing line between the 

 protoclastic gneiss and the cataclastic-protoclastic gneiss cuts 

 directly across the banding and foliation, it is apparent that the 

 active forces came from without and had nothing to do with flowage 

 within the magma. 



The alternative to the foregoing outline is to assume that the 

 foliation of the whole complex is the result of recrystallization and 

 that it has subsequently been subjected to a wave of crushing which 

 was accompanied by recrystallization of quartz under a limiting 

 set of conditions. Such an assumption involves the idea that 

 recrystallization may result in exactly the same phenomena which 

 it is known do arise during the intrusion and crystallization of a 

 magma. This hypothesis needs support and proof from other 

 districts to be considered here. It may be added here that the 

 brecciation of part of the rock was either a process of dry crushing, 

 since no hydro thermal minerals were formed, or else the crushing 

 took place under magmatic conditions so that magmatic minerals 

 formed, which is the hypothesis favored. 



It is realized that the conclusions set forth here are drawn from a 

 limited field and may need to be modified by evidence from other 

 districts or by future work-. The conclusions are therefore not 

 considered so important as the facts presented relative to the areal 

 distribution in zones of rocks showing similar degrees of metae 

 morphism and to the character of the metamorphism within thes- 

 zones. 



