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Chapter 3: Geologic Structure and Landforms

3.101: Part of the Lauder Sand Hills Northwest of Lauder

Sand deposited into Lake Hind in southwestern Manitoba was exposed to wind action when the lake retreated. Sand dunes have been formed in this area north of the Souris River 1 that flows to the east across the southern edge. The dunes are mainly northwest/southeast trending ridges in response to the prevailing winds. Most are stabilized, but bare sand can be seen at several locations 2. The vegetation cover consists of grasses—light-toned with smooth texture 3—and deciduous woodland, which is darker-toned with mottled texture 4. A marked vegetation difference exists on either side of the dune ridges. The south side with a dry microclimate is either bare or grass covered 5, whereas the wetter north-facing side is wooded 6. A few patches of land have been cleared for agriculture, the sandy nature of the soil being indicated by light tones 7. The Souris River meanders across the southern edge. Steep river cliffs, sometimes cut into dunes 8, occur on the outside of bends, and light-toned point bars appear on the inside 9. Meander scrolls are also visible on the insides of meander loops 10. Two old cutoffs 11, and one more recent 12 can be seen.

Land south of the river has been cleared for agriculture; the results of harvesting can be seen in one field 13 with rectangular straw stacks 14 and a pile of loose straw 15. Farm buildings are visible at 16.

Figure 3.101: Part of the Lauder Sand Hills Northwest of Lauder

Figure 3.101: Part of the Lauder Sand Hills Northwest of Lauder

Figure 3.101

Vertical air photograph: A16410-112

Flight height: 10,500 feet a.s.l.; lens focal length: 152.63 mm

Date: October 28, 1958

Scale: 1:17,500 (approx.)

Location: Townships 5 and 6; Ranges 24 and 25 WI

Map sheets: 1:250,000 62F Virden

1:50,000 62F/7 Hartney