97 



Kilometres n *^ s of the Coteau can be seen rising somewhat 



abruptly from the level prairie. These hills 



are the erosion remnants of Tertiary deposits. 



South of Moosejaw are exposures of white 



silts and clays, and important deposits of fire 



clay. Coal seams also occur in these measures. 



424 m. Mortlach — Altitude 1975 ft. (602 m.). The 



682 km. cuttings along the railway here show deposits 



of boulder clay in irregular shaped hills. Small 



pebbles occur in the clay, and large boulders 



appear at the surface. 



433 m. Parkbeg — Altitude 2062 ft. (628 m.). The 



697 km ascent to the third prairie steppe is made 



through a gap in the hills of the Coteau, 



and glacial drift is much in evidence which, 



however, here shows an admixture of material 



derived also from the underlying sandy beds. 



Six miles (9.6 km.) west of Parkbeg the boulder 



clay encloses a body of sandstone evidently 



removed from the rocks beneath. Morainic 



material is spread all along the eastern face 



of these hills, and it is still an open question 



whether the drift farther west was deposited 



by floating ice or by a farther advance of the 



glacial ice front. 



508 m. Swift Current — Altitude 2,420 ft. (736 m.). 



817 km. Beyond Parkbeg the railway follows the plain 



which slopes northward from Cypress hills and 



which is underlain by rocks belonging to the 



Pierre division of the Cretaceous. At Forres 



station 



612 m. Forres — Altitude 2,465 ft. (751 m.). the Belly 



985 km. River 



series comes to the surface, and the rocks of 



which it is composed outcrop in the hillsides 



all the way to Medicine Hat. Sections of 



these rocks are best seen at Redcliff on the 



noith side of the valley of South Saskatchewan 



river. Near the town and to the east of it the 



river banks show a great thickness of till. 



656 m. Medicine Hat — Altitude 2,168 ft. (661 m.). 



1,056 km. Natural gas has been found in the lower part 



of the Belly River series and also in the sandy 



beds of the continuation of the Dakota. At 



35069—7 



