Camhro-Ordovician Section in the Beaverfoot Range. 459 



Mount Bosworth. 



Beaverfoot Range. 

 Exposed top. Beaverfoot formation 

 (" Halysites limestone ") of Riciimond 

 age (l).i 

 Glenogle shales (" Graptolite shales') of 

 Chazyan (Normanskill) age, with shales 

 of Canadian age (2) ' innuediately below 

 and almost insej^arable from them. 

 Goodsir shales ranging in age from 

 Canadian or pre-Canadian at the top to 

 true Ui:)per Cambrian (that is, lower 

 than Ozarkian) at the base (3) ^ ± 6,040 

 feet (Allan). 

 Ottertail limestone of UpjDer Cambrian 



age +1,72.5 feet (Allan). 

 Chancellor formation of Ujjper Cambrian 

 age + 4,500 feet (Allan). 



Exposed top (4).^ 



Sherbrooke formation of Upper 



Cambrian age (5).^ 

 Paget formation of Upper Cam- 

 brian age. 

 Bosworth formation of Upper 



Cambrian age (6).^ 

 Eldon formation of Middle Cam- 

 brian age. 

 Stephen formation of Middle 



Cambrian age (7).^ 

 Cathedral formation of Middle 



Cambrian age. 

 Mount Whyte formation of 



Middle Cambrian age (8).^ 

 Lower Cambrian. 



Notes on the Correlation Tabic. 



(1) The change in the reference of these beds from Silurian to 

 Richmond is discussed in this paper, § 7. 



(2) The inclusion of both the Normanskill and the Canadian 

 horizons within the limits of the Glenogle shales is discussed in this 

 paper, § 15. 



(3) The Upper Cambrian horizon at the base is the one carrying 

 the fossils described by Walcott as " Ceratopyge ". The change in 

 the systemic reference of this fauna is discussed in this paper, § 16. 



(4) The relations of the Chancellor formation at the base of the 

 section in the Beaverfoot and Ottertail Ranges to the Sherbrooke 

 formation in Mount Bosworth and Mount Dennis are difficult of 

 determination. The base of the Chancellor formation itself is 

 described by Allan ^ as consisting of " highly sheared grey shales, 

 slates, argillites, and phyllites". These outcrop in the valleys 

 where erosion has exposed them and are estimated to be 4,500 feet 

 thick, but while several of the mountauis expose the Sherbrooke 

 formation in their summits, the relations to the overlying Chancellor 

 shale series has not been observed. 



^ These numbers refer to the notes which follow. 



2 Sumrn. Rep. Geol. Surv. Canada for 1912, 1913, p. 168. 



