154 



INDEX TO THE STRATIGRAPHY OF NORTH AMERICA. 



M-N 11. 'ROCKY MOUNTAINS OF CANADA. 



The stratigraphy of the Canadian Rockies was originally described by McCon- 

 jjg^^559e ^Yio distinguished the Bow River and Castle Mountain groups. Walcott ^^^ 

 has recently studied these rocks and divided them into several formations. He 

 says: 



Mr. McCoimell proposed the name "Castle Mountain group" for the great series of lime- 

 stones and shales between the quartzitic sandstones and siliceous shales of the "Bow River 

 group" below and the superjacent Ordovician graptolitic shales on the west and Banff lime- 

 stone on the east. This includes the upper portion of the Lower Cambrian fauna at the base 

 and the lower portion of the Ordovician fauna at the su m mit. The term "Castle Mountain" 

 is useful for the series, but I think that local names can be applied with advantage to several 

 of the formations of the "Castle Mountaia group" as originally defined. The foUowiag table" 

 gives the relative positions and thicknesses of the new formation names herein proposed and 

 defined for the Canadian Rocky Mountain section: 



Oambrian formations of the Canadian Rocky Mountains. 



[o In the book cited, through a typographical error, the Mount Whyte formation was placed in the Middle Cam- 

 brian in the table on page 2, but the fauna was recognized by Walcott as Lower Cambrian, and is so termed on page 4.] 



[6 The St. Piran and the two underlying formations compose the upper part of the Bow River group. In 1910 

 Walcott found a conglomerate at the base of the "Fairview formation," recently renamed by him the Port Mountain 

 sandstone (Mon. U. S. Geol. Survey, vol. 51, 1912, p. 131),_ that marks an unconformity between it and the underlying 

 part of the Bow River group, which is very much the thicker portion. He therefore regards the Bow River group as 

 chiefly pre-Cambrian. (Personal communication.)] 



o The table as here printed is not an exact quotation but is made up from Walcott' s paper. — B. W. 



