148 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 75 



INTRODUCTION 



In the progress of my reconnaissance in western Alberta and 

 eastern British Cokniihia of the pre-Devonian formations of the 

 Rocky Mountains from the Saskatchewan River drainage south to 

 the Hne of Crows Nest Pass, many interesting problems appeared, 

 for the detailed study of which there was but little time in the field. 

 One of the most insistent of these was the problem of the location 

 and extent of the original areas of deposition of the sediments now 

 forming the series of stratigraphic formations between the ])rc- 

 Cambrian and the Devonian. Much time and effort were devoted to 

 collecting fossils from the Cambrian and Ozarkian rocks in order 

 to obtain data that could be relied on regarding an area where irregu- 

 larities of sedimentation, and subsequent displacement of strata by 

 faulting and folding, had greatly complicated the normal stratigraphic 

 succession of the formations. At first, with the great section of 

 McConnell on the line of the Canadian Pacific Railway ' as a guide 

 (fig. 18), I considered that the entire series of sediments had been 

 deposited in a broad seaway that filled the Cordilleran Geosyncline 

 in upper Lower Cambrian time and that this seaway gradually nar- 

 rowed as it received sediments from the great hinterland to the west 

 and east until Devonian time. This impression was strengthened in 

 studying the Glacier Lake-Saskatchewan River section, and in 1924 

 I published a transverse theoretical section of the Cordilleran Trough, 

 based on conclusions reached at that date.^ The section may possibly 

 be a fairly correct one for the Glacier Lake- Saskatchewan area, but 

 it does not now afford a satisfactory explanation for the Bow-Kicking 

 Horse River section, 60 to 70 miles (96.5 to 112.6 km.) to the south- 

 southeast. 



The object of this paper is to call attention to conclusions based 

 on further field studies and the working over since 1924 of a consid- 

 erable amount of unpublished geological and paleontological data on 

 the formation of the Cordilleran Geosyncline, located in the drainage 

 areas of the Bow, Kicking Horse, and Saskatchewan Rivers. 



The boundary between the Bow and Goodsir Troughs should be 

 drawn about one-fourth of an inch to the west (left) where it 

 crosses the Kicking Horse River, near Field (F on map) and con- 



*Geol. and Nat. Hist. Surv. of Canada, Ann. Rep. for 1886, 1887, Ft. D. 

 pp. 15D-31D, and accompanying colored section. 



' Soc. Geol. de Belgique. Livre Jubilaire 1924. La Discordance de Strati- 

 fication et la Lacune Stratigraphique Pre-Devonienne dans les provinces 

 Cordilleres d'Alberta et de Colombia Britannique, Canada. 



