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Chapter 3: Geologic Structure and Landforms

3.50: Patterned Ground Moraine Near Deloraine

The light-toned circular areas 1 are ice disintegration ridges, formed as ice became stagnant. A probable explanation of their origin is that as ice became stagnant it broke into blocks; sediment within the ice slid down the sides of the blocks as they melted, accumulating as a circular ridge at the ice margin. The resulting ridges are only about 2-3 metres above the surrounding countryside and are barely visible on the ground. They are light-toned because rain splash and wind erosion have removed fine-grained and organic materials from the slightly elevated crests. Their appearance on the photo is enhanced by the fact that almost all the natural vegetation has been removed for agriculture and many fields have been left fallow 2. The circles are not so obvious in fields that are cropped 3. Fields devoted to grain crops are light-toned with a distinctive harvesting pattern 4. The only surface drainage is a small intermittent stream (Medora Creek) 5 that eventually flows into the Souris River west of this area. An artificial drainage ditch 6 enters the creek from the south.

The land in this area is devoted mainly to arable farming: nine farms 7 can be seen in this area of 6.25 square miles (16.2 square km). Typically in this very flat area the farmhouses are protected by shelterbelts 8, built to shield them from cold north and northwest winds in winter. In this dry area there is little surface water, so dugouts 9 have been constructed for farm water supply. Section lines 10, often with gravel roads along them 11, are clearly visible, and quarter sections 12 can sometimes be picked out from land use differences. PTH 21 between Deloraine and Hartney 13 runs north/south through the area. The oval-shaped feature in the southeast corner is the Deloraine racetrack 14. Harness racing is a favourite summer activity in many small communities in southern Manitoba.

Figure 3.50: Patterned Ground Moraine Near Deloraine

Figure 3.50: Patterned Ground Moraine Near Deloraine

Figure 3.50

Vertical air photograph: A16391-97

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

Date: October 13, 1958

Scale: 1:17,600 (approx.)

Location: Township 3; Range 23 WI

Map sheets: 1:250,000 62F Virden

1:50,000 62F/2 Waskada