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Table of Contents
Foreword
Preface
Glossary

Chapter 3: Geologic Structure and Landforms

3.26: Glacial Spillway and the Meandering Assiniboine River North of Virden

The Assiniboine River occupies a steep-sided, flat-floored glacial spillway about one to one and a half miles (1.6 to 2.4 km) across at its base. Cutoffs can be seen at several locations 1, and a segment of the river has also been abandoned 2. Another small cutoff is imminent 3. The two most clearly defined cutoffs 4 were in existence when the original DLS maps were made in 1873. Neither now receives water from the main river channel, but in both cases when they contain a lot of water it flows out from them to the river. In both cases enough time has elapsed since abandonment for trees to grow across the meander neck 5.

Both sides of the spillway are wooded, and steep-sided mainly wooded gullies dissect both the west bank 6 and east bank 7. Woodland (dark-toned) can also be seen skirting the river channel 8, but further back on the floodplain land has been cleared for agriculture 9.

On either side of the spillway land is flat. On the west side there are extensive areas of scrubland with tree clumps 10 developed on sandy outwash deposits. Further west and also east of the spillway, land is devoted to agriculture 11. Light-toned hummocks can be seen in many of the fields 12.

The section lines of the DLS system are obvious with north/south 13 and east/west 14 gravel roads along some of them, although in some locations the road direction is influenced by the topography 15. One road runs obliquely down the valley side and then along the spillway just above the floodplain 16. The CP line, totally unrelated to the survey system, can be seen at the western edge of the photo 17.

Figure 3.26: Glacial Spillway and the Meandering Assiniboine River North of Virden

Figure 3.26: Glacial Spillway and the Meandering Assiniboine River North of Virden

Figure 3.26

Vertical air photograph: A24966-242

Flight height: 15,433 feet a.s.l.; lens focal length: 85.32 mm

Date: June 18, 1978

Scale: 1:52,800 (approx.)

Location: Township 12, Range 25 WI

Map sheets: 1:250,000 62F Virden

1:50,000 62F/15 Virden

62K/2 Hamiota