
CRETACEOUS AND TERTIARY—MILK RIVER. 117 
occurrence of amber shows that coniferous wood, which composes so 
large a part of the clearly Tertiary lignites, was here going to decay If 
then it be granted that these beds are lower Cretaceous, the possibility of 
the occurrence’? of beds of fossil fuel in the rocks of that age, in this 
region, would be established. » 
285. The strike of these beds is N. 27° E., (mag.) and their dip, 
south-eastward, at angles varying from 45° to about 30°. The tilting of 
strata to such angles as these—even if the existence of no more violent 
flexure be suspected—is in itself a circumstance sufficiently remarkable, in 
a country where, for hundreds of miles, the rocks are found with inclina- 
tions no greater than can be accounted for by original irregularities of 
deposit. The nearest disturbed region is that in the neighbourhood of 
the Buttes, and the upturning is there in immediate connection with the 
extrusion of igneous matter. 
286. The valley of the West Fork of Milk River, though showing 
some scarped banks, does not penetrate below the drift. 
287. Two and a half miles beyond_West Fork, exposures of sombre 
Cretaceons clay-shales of the usual character were again met with, and 
the barren plain is based on these rocks for about twenty miles west- 
ward. Immediately west of the West Fork, a well-marked plateau runs 
up nearly to the Boundary-line, from the south, and no doubt marks the 
overlap of Tertiary rocks, which are again met with in full force in the 
high ground around Milk River. On approaching this stream, a line of 
small lakes * and swamps, is found along the eastern base of a plateau, 
which runs north-westward, and on the Line has a breadth of six miles, 
east of the river. Near the edge of the plateau the clay plain shows 
extensive superficial deposits of loose sands, which have probably been 
derived from the disintegration of the soft sandstones of division y., 
equivalent to the Fox Hill group. 
288. The valley of the Milk River is one of the most important 
features met with on the line of the forty-ninth parallel, and offers con- ° 
tinuous and magnificent sections of beds referable to the Lignite Tertiary 
series. The country on both sides of it, is seamed with tributary ravines 
and gorges, the banks of which are often nearly perpendicular, and which 
ramify in all directions. Where the Line crosses the river valley, it is 
utterly impassable for waggons or carts, and near this place the Great Dry 
Coulée branches off, which, according to Palliser’s map, runs to Lake 
* Known to the half-breed hunters as Lacs des Marrons. 

