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common type of agglomerate appears to be merely a brec- 

 ciated Keewatin trap or andesite which grades into sericite 

 schist. This rock is usually light coloured, and is well 

 developed near the Keweenawan dyke on the unnamed 

 island west of Queer island. Through a cartographic error 

 this outcrop was shown on the older maps as clay slate. 



Agglomerate; Kenora, Ont. 



The other principal type of agglomerate is also a breccia, 

 but in this case the brecciation is probably caused by a 

 flow of dark lava which has broken off fragments of solid 

 rock and cemented them together. It is possible, however, 

 that this type is due to the falling of volcanic bombs and 

 ash into molten lava, though the gradation from the 

 ellipsoidal trap to agglomerate on the east side of Ash 

 bay would strengthen the former suggestion. This type of 

 agglomerate is well exposed near the old saw-mill in 

 Kenora. 



Altered Traps, Hornblende Schists and Chlorite 

 Schists. — These rocks, which are by far the most widely 

 distributed of the Keewatin rocks in this region, are prob- 

 ably all of the same origin. In general it may be said that 



