TINTAH BEACHES IN MANITOBA. 405 



quarter of section ;">, townsliip 2, this shore bears scanty deposits of beach 

 gravel and sand, witli their crest at 1,110 to 1,115 feet. The lower Tintah 

 beach lies a third of a mile farther east, and is a distinct ridge of gravel 

 and sand with its crest at 1,083 to 1,085 feet, bordered on each side bj^till, 

 the surface of which is 5 feet lower on the east and 3 feet lower on the west. 

 Thomas Kennedy's well, 14 feet deep, in the northeast quarter of section 5, 

 township 2, range 5, found the till only 4 feet deep, underlain by the Fort 

 Pierre shale. This terrace doubtless owes its form, like the far more prom- 

 inent Pembina Mountain, to preglacial erosion of these Cretaceous beds. 

 It continues along the foot of the mountain, with a width of 1^ to 2 miles, 

 at least to the South Branch of Tobacco Creek, which crosses it near Miami 

 post-office, 25 miles north of the international boundary. Throughout its 

 whole extent it has a considerable ascent upon its width from east to west, 

 as in the localities noted. Much of its surface is till with many bowlders, 

 but some poi'tions have no bowlders, such tracts being overspread with 

 lacustrine gravel and sand, oi- perhaps occasionally consisting of Cretaceoiis 

 shale next below the soil, with no drift or lacustrine deposit. 



A mile west of Morden the escarpment bordering this terrace has an 

 ascent of about 40 feet, with its top approximately 1,070 feet above the 

 sea. Within an eighth of a mile to the west is the lower Tintah beach, a 

 small ridge of gravel and sand which has been excavated for vise in plaster- 

 ing, its crest being at 1,085 feet, nearly, with a descent of 5 or 6 feet from 

 it to the east and 2 or 3 feet to the west. It extends a considerable distance 

 nearly parallel with the verge of the terrace. The road thence to Thorn- 

 hill ascends slowly in tlie next 2 miles across a somewhat uneven surface 

 on which eight or ten beach ridges are discernible, belonging' to the upper 

 Tintah, Norcross, and Herman stages. 



The most remarkable feature of this tract is its extraordinary abun- 

 dance of bowlders, nearly all Archean, usually less than 5 feet in diameter, 

 but in many places ranging in size to 10 feet or more. Upon an area that 

 extends at least 1 to 2 miles both south and north of the road and railway 

 the surface is as thickly strewn with bowlders as are the most typical ter- 

 minal moraines seen by me in Minnesota and South and North Dakota. 

 Many of these rock masses, instead of being embedded in the drift, as is 



