THE ASSINIBOINE DELTA. 371 



stretches northwestward from Braudoii, Chater, and Doug-las to the Little 

 Saskatchewan and Oak rivers. From Brandon to Douglas the boundary of 

 the delta is close north of the Assiniboine and the Canadian Pacific Rail- 

 way; but at Douglas the line dividing the delta sand and gravel and tlie 

 adjoining surface of till turns north-northeastward and extends about 20 

 miles in a nearly direct course toward Neepawa, then bends northward in 

 the east part of townships 13 and 14, range 16, and crosses Stony Creek 

 a few miles west of Neepawa. Between Brandon and the mouth of the 

 Souris the delta i-eaches 3 or 4 miles southwest of the Assiniboine, being 

 there also bordered by a smoothly undulating or rolling tract of till, but 

 the morainic Brandon Hills rise prominently within a few miles farther 

 west. From the Souris east to the Cypress, a distance of nearly 25 miles, 

 the southern margin of the delta is similarly divided from the Tiger Hills 

 by a belt of undulating and rolling till which averages about 5 miles in 

 width. Farther to the east the delta deposits abut directly upon the north- 

 ern base of these hills from the Cypress River, by Holland and Treherne, 

 to the north end of the Pembina Mountain. Thence to the southeast the 

 head streams of the Boyne, after their descent from the plateau of the Pem- 

 bina Movmtain, cross the southeastward extension of this delta to Almasippi. 

 This portion, however, is not probably a part of the delta as it was at fii-st 

 deposited, but has been derived from the erosion of the eastern front of the 

 original delta by the waves of the lake in its later and successively lower 

 stages, being transported thence southward by shore currents. The same 

 lacustrine action has doubtless extended the delta of gravel and sand gen- 

 erally 5 to 15 miles eastward beyond its original area, thereby giving its 

 eastern face a more gradual slope. As thus enlarged its east boundary 

 runs north from Almasippi to Poi-tage la Prau-ie, curving eastward between 

 these places, and thence it passes west-northwest to near Gladstone, Arden, 

 and Neepawa. The eastern base of the delta, where it adjoins the flat 

 expanse of the Red River Valley and the country bordering the lower 

 Assiniboine and Lake Manitoba, has an elevation of 850 to 900 feet above 

 the sea; while the high delta plateau, which was submerged only about 50 

 feet or less by the lake when it was being deposited, and was in part shoals 

 and low islands, has an elevation of from 1,200 to 1,275 feet above the sea. 



