IQi 



H. C. COOKE 



The rocks directly overlying the conglomerate are drift-hidden, 

 but the next outcrops to the north are of mica gneiss and horn- 

 blende gneiss, which probably represent the recrystallized product 

 of sandy shales. To the north of this, beds of altered impure 

 sandstone and grit are found, beyond which mica and hornblende 

 gneisses again appear. The latter rocks continue to outcrop to 

 the northern limit of the area, where they are intruded and cut 

 ofif by granite. 



Fig. 9. — Conglomerate about a mile below the mouth of the Brock River 



The rocks of the area were determined from observations on a 

 number of drag folds, to form the south limb of a syncline or the 

 north limb of an anticline. The axial planes of secondary drag folds 

 were observed to dip toward the north. Hence the folding is of 

 the abnormal type. The axes of these drag folds plunge, where 

 observed on the Brock River, about 22° to the west. Hence the 

 plunge of the primary fold at this point is to the west. The general 

 strike of the axes of these drag folds is N. 80° to 85° E. 



About twenty-five miles down the Chibougamau River, near the 

 mouth of the Opawika, another wide area of rocks similar to the 

 upper beds of this series of sediments outcrops. The basal con- 

 glomerate, however, was not found here, so that it is possible that 



