32 G. M. DAWSON — GLACIAL DEPOSITS OF SOUTHWESTERN ALBERTA. 



acter entirely tentative. In the following notes his ])urpose is raereh^ 

 to amplify previous observations on a particularly interesting part of this 

 western reo;ion by the addition of new facts, given, as far as possible? 

 apart from any theoretical considerations whatever. In the concluding 

 pages, however, an attempt is made to indicate the more obvious deduc- 

 tions which appear to flow directly from the examination of the particular 

 district in question. 



In a report by the writer on the southern portion of the district of 

 Alberta,* the principal facts then ascertained of the " superficial geolog}'' " 

 are given, but the work upon which that report was based was directed 

 chiefly to the " solid geology " of the country, and details respecting the 

 superficial geology were as far as possible eliminated in the interests of 

 brevit3^ Since the publication of that report great advances have been 

 made in our knowledge of the glacial phenomena of the nortliern part 

 of the continent, some of which seemed to render the region particularly 

 referred to in this paper one of especial importance as the meeting place 

 of the deposits (whether immediately or proximately deriv^ed) of the 

 Cordilleran and Laurentide ice-sheets. Thus it became desirable that 

 an attempt should be made to further investigate this region and to test 

 the previous observations and conclusions. With this object in view, a 

 couple of weeks in the earl}^ part of the summer ot" 1894 were devoted 

 chiefly to a critical examination of the superficial deposits of that part 

 of southwestern Alberta adjacent to the eastern slopes of the Rocky 

 mountains. The writer was accompanied by Mr R. G. McConnell, who 

 had previously acted as his assistant in the same field, and, while he as- 

 sumes the responsibility for the statements made in the sequel, those 

 observations made by Mr McConnell will be given under his own name 

 and in his own words. He would further take this opportunity of ac- 

 knowledging the value of Mr McConnell's cooperation, and of stating that 

 in regard to the ol)scrvations of fact, at least, there is complete unanimity 

 between himself and that gentleman. 



Physical Features of the Region. 



The region treated of may be described as extending from the inter- 

 national boundary northward to Bow river, or in latitude from 49° to 

 51° 20'. The eastern edge of the Rocky mountains proper (Laramide 

 range) is defined b}^ the line separating the Paleozoic rocks from those 

 of the Cretaceous and Laramie, and, although this line is not a perfectly 

 definite one, it corresponds closel}^ with the orographic features, and the 

 eastern front of the mountains is often particularly abru[)t and striking.. 

 The want of definiteness referred to arises from the fact that embayments 



* Report oil the Geology of the Bow and Belly Rivers region. (Jeol. Survey of Canada, 1882-'.S4. 



