
my) - GENERAL OUTLINE OF THE GEOLOGY. 
hs 
14% 
17 
doubt Laurentian. The general course of the eastern outcrop is conse- 
‘a 
- 
2 














quently about north-north-east ; and it is marked, broadly, by a series of 
escarpments and elevations, including—from south to north—Pembina, 
Riding, Duck, Porcupine and Basquia Mountains. All these appear to 
be composed for the most part, if not entirely, of Cretaceous rocks, though 
the extreme edge of the formation may often stretch beyond them. 
These so-called “ Mountains” 
shown—salient points of the edge of the second plateau, and the generally 
are, more correctly speaking—as already 
horizontal position of the beds thus suddenly cut off to the cast, attests 
the immense denudation which must have taken place in comparatively 
modern times. ; 
31. North of the Basquia Mountain, from the very scanty informa- 
tion we at present possess, the edge of the Cretaceous would appear to 
run westward and cross the Saskatchewan River near Fort a la Corne, 
where at Cole’s Falls a dark-coloured shale which has been referred to 
the lowest member of the series, occurs. It may very probably be nearly 
conterminous with the edge of the second plateau, which, according to 
Mr. Selwyn, crosses the river forty-five miles below the Fort. The 
western border of the Cretaceous seems in some places to follow closely 
along the base of the Rocky Mountain Range, but many circumstances 
arise to complicate the question in that region, and it will only be after 
the accumulation of much more information than is at present in our 
possession, that the line can be laid down with any accuracy. In some 
parts of the range, Cretaceous rocks have been included among the 
mountains themselves, and considerably altered; but the greater part of 
the newer strata, which must have covered the paleozoic rocks of this 
region when the uplift first took place, have been removed by denudation. 
32. The Cretaceous rocks thus defined in breadth, north of the 
Boundary-line, have been noted by Prof. Hind, Dr. Hector, Mr. Selwyn 
and Prof. Bell, in many localities on the second prairie level, some of which 
are more particularly referred to in the sequel; and are known to extend 
in a broad zone from the North Saskatchewan to the Mexican frontier 
and southward. In the western Territories of the United States, the 
stratigraphical sequence and paleontology of the Cretaceous beds, have 
been carefully studied by Dr. Hayden, Professors Cope, Newberry, 
Marsh, Lesquereux, Leidy and others. South of the forty-ninth parallel, 
however, the Cretaceous itself is to a great extent concealed by deposits 
of Tertiary age, which, though they have been accumulated at different 
periods, from the generally undisturbed nature of the country, are rarely 
2D 


