GEOLOGY OF THE SCHROON LAKE QUADRANGLE 



47 



sharp. Immediately above this Keene gneiss, but not in very sharp 

 contact with it, is a very gneissoid granite (nos. 34 and 35 of 

 table 2) which contains many garnets. This gneissoid granite 

 grades upward into typical, medium grained, only moderately 

 foliated granite without garnets. A similar typical granite lies 

 against the Keene gneiss at the bottom, but the contact there is 

 quite sharp. The writer's interpretation is that the upward moving 

 granite magma more or less assimilated some Marcy or Whiteface 



Fig. 3 Sketch of part of the great ledge at the southern brow of Cobble 

 hill showing Keene gneiss in its relation to both granite and Whiteface 

 anorthosite. Contacts between the Keene gneiss and both Whiteface 

 anorthosite and garnetiferous granite are not sharp, but the contact between 

 the Keene gneiss and the lower granite is rather sharp. 



anorthosite at a considerable depth, and that this molten mass 

 (Keene gneiss magma) rose still higher and caught up and only 

 partly fused the borders of fragments of Whiteface anorthosite. 

 The origin of the garnetiferous granite is not so certain, though it 

 may represent a mass of granite with a small quantity of anortho- 

 site very thoroughly digested. 





