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which is considerably brecciated and evidently resulted by 

 recrystallization of the ancient traps. This type of material 

 is to be seen near the Sultana mine and on the west side of 

 Bottle bay, where domes of granite show nearly every 

 possible phase of this rock from the slightly altered trap 

 with pillow structure to the brecciated hornblendic rock 



Brecciated contact, Keewatin and granite. Sultana mine. 



included in domes of granite. Sometimes even the granite 

 domes are free from it except near their margins. To the 

 west of the small indentation on the north side of Andrew 

 bay, several of these granite domes, with the brecciated 

 hornblendic rock grading into the ancient traps, are to be 

 found. These domes have the typical "roches moutonnees" 

 structure and have evidently been denuded by glaciation, 

 but it is of interest to note that the resultant form has been 

 determined not by the ice but by the original intrusion of the 

 granite. Examples of this structure are extremely common 

 in other parts of Lake of the Woods particularly along the 

 shore of Grande Presqu'ile. These however are beyond 

 the limit of the excursion. 



