NO. I FORMATIONS OF BEAVERFOOT-BRISCO-STANFORD RANGE 4 1 



Ozarkian. — The comparison with the Mons formation at the type 

 locality at Glacier Lake with the Sinclair Canyon section more than 

 100 miles (160.9 km.) to the south shows the two to be similar both 

 in lithology and faunas, except that the Sinclair Canyon section is 

 nearly 2.5 times as thick. The character of the limestones and shales 

 and the succession of the sub-faunas is the same, also the stratigraphic 

 position. 



Cambrian. — The Mons shales are superjacent to a thick series of 

 magnesian limestones (Lyell) at Glacier Lake and other sections 

 north of the Bow Valley, and the same conditions appear in the 

 Stanford Range at Sinclair Canyon, Fairmount Hot Springs, and 

 Sabine Mountain. 



I think we are justified in extending the names Mons and Lyell of 

 the northern sections to similar formations south of the Kicking Horse 

 Canyon into the Beaverfoot-Brisco-Stanford Range. 



The continuity in the Cordilleran sea of the sediments now consti- 

 tuting these formations in the " Rocky Mountain Trench " appears to 

 have been along its western side in British Columbia, which is now 

 west of the Continental Divide. 



ORDOVICIAN-SILURIAN BOUNDARY 



I had not given much attention to the discussion over the " Ordo- 

 vician-Silurian Boundary " prior to my present study of the forma- 

 tions of the Beaverfoot-Brisco-Stanford Range, but when I found in 

 the Sinclair Canyon section that a quartzite was superjacent to an 

 arenaceous shale (Sinclair) containing graptolites of lower Ordo- 

 vician (Beekmantown) age and that superjacent to the quartzite a 

 massive limestone (Beaverfoot) contained a large and representative 

 Richmond fauna, I realized that I was at the parting of the ways and 

 must include the Beaverfoot in the Ordovician and thus agree with 

 the " conservatives " in the controversy, or place it in the Silurian and 

 agree with the " progressives." Not having any great interest for or 

 against any particular interpretation, I returned to the field in 1923 

 with the desire to discover more of the record of what happened prior 

 to the deposition of the Beaverfoot formation with its contained 

 " Richmond " fauna. The section in Sinclair Canyon was re-examined 

 and the line of contact of the Beaverfoot with the formations above 

 and below observed wherever accessible in the Brisco-Stanford Range 

 for 60 miles (96.5 km.) or more. In all sections there appeared to be a 

 conformable contact between the Beaverfoot and superjacent Brisco 

 formations. The Beaverfoot limestones are of a lighter gray color 



