100 



Kilometres t> e ds occur. A narrow westerly dipping fringe 

 of the coal bearing beds is being mined below 

 the surface at this point. Behind the town, 

 cliffs of Devonian and Carboniferous limestones 

 show the eastern edge of the succeeding fault 

 block. 



916 m. Bankhead — Altitude 4,569 ft. (1393 m.). 



1,474 m - I n front of Cascade mountain the continuation 

 of the coal measures forms a buttress in which 

 the beds dip towards the fault line. Mining is 

 carried on by an entry driven from the valley 

 level. The cross-cut tunnel from this entry 

 cuts the measures and intersects several seams. 



The measures in which these seams occur 

 constitute a block dipping to the southwest 

 toward Cascade mountain. At the south end 

 of the block they pass under the limestone. At 

 the north end, up Cascade river, the measures 

 are bent up in a syncline, but further on 

 they have been entirely eroded away. 



A section measured near the mine at Bank- 

 head gives a total thickness of 2,800 feet (853) 

 of possibly coal bearing rocks, with 550 feet 

 (167 m.) of thin bedded brown sandstones 

 and shales above them. The measures consist 

 of sandstones and shales of a generally brown 

 colour, and, in this vicinity, three of the heavy 

 sandstone beds form strong ribs. The upper 

 and lower sandstone ribs seem to define the 

 upper and lower limits of the coal formation, 

 which has a thickness of 1,100 feet (335 m.). 

 Below is a series of sandstones and shales 

 very similar to those higher up. The passage 

 to the Fernie shales is conformable, and is 

 marked by an absence of sandstone. The 

 Fernie shale consists of 1,360 feet (445 m.) 

 of dark grey to black shale overlying 240 feet 

 (73 m.) of dark greyish thin-bedded sandstone, 

 the whole of marine origin and assigned to the 

 Jurassic period. These beds are exposed on 

 the river sides above the mine. 



