256 Burling — Pur cell Range and Rocky Mountains. 



Summary Eept. Geol. Survey Canada for 1915, pp. 98-99, 

 1916). This places them fairly well down in the Upper 

 Cambrian instead of in the Ordovician. Less than one 

 mile east of Golden, in the gorge cut by the Kicking Horse 

 Eiver, the writer has collected Normanskill graptolites 

 similar to those discovered by McConnell at Glenogle, 15 

 miles farther to the east. 



We have, therefore, close together in the Rocky Moun- 

 tain (Columbia Eiver) trench at Golden, and within the 

 single shale series which we have described as separating 

 the elastics of the Pur cell Eange from the calcareous 

 rocks of the Eocky Mountains, indisputable evidence of 

 the presence of strata representing the Middle Cambrian, 

 the Upper Cambrian, and the Ordovician. 



This Cambro-Ordovician shale series is closely folded 

 and micaceous in places, and we have no evidence regard- 

 ing the thickness of strata here intervening between 

 the Middle Cambrian and Ordovician horizons above 

 described, but we do know that the same faunal horizons 

 are, in the Eocky Mountains less than 30 miles to the 

 east, separated by many thousands of feet of massive 

 limestones. 



The conclusion we are about to draw must already be 

 evident to the student but it will be necessary first to 

 speak of Daly's correlations of the rocks in the Purcell 

 Eange with those in the Eocky Mountains. By him the 

 thick elastics of the Purcell Eange are correlated with the 

 clastic basal or lower Cambrian portion only of the Eocky 

 Mountains section, a correlation based upon so much 

 study, both in the field and office, that we have hesitated to 

 question it. But the only gap in the evidence we have in 

 favor of a different conception of the relations is the fail- 

 ure, so far, to find Middle or Upper Cambrian fossils in 

 the Purcell Eang"e elastics. And the other evidence is so 

 strong that we would suggest the view that the deposition 

 of the elastics of the Purcell Eange (western), the shales 

 of the Eocky Mountain trench (central), and the dom- 

 inantly calcareous rocks of the Eocky Mountains (east- 

 ern) was essentially contemporaneous and that the 

 stresses to which the central shales have been subjected 

 has been relieved by crumpling in the shales themselves 

 and by the overthrusting of the more competent but 

 equivalent strata to the west. 



London, England. 



