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Table of Contents
Foreword
Preface
Glossary

Chapter 2: Location, Borders, and Lakes

2.3: Lakes of West Central Manitoba

On this LANDSAT image the radiation recorded from the earth’s surface is processed so that vegetation appears red/brown and water bodies appear as shades of blue.

In the southwest is Riding Mountain National Park 1 with orange/brown patches 2 representing coniferous woodland (radiating infrared radiation at the time of the image). A lighter coloured area in the west 3 is the location of a forest fire that destroyed much of the vegetation. Also seen is the eastern edge of Duck Mountain 4 with some patches of coniferous trees 5. Another area of coniferous woodland (red/orange) can be seen in the northeast 6.

North-northwest/south-southeast lineations in the north 7 are grooves etched by southward moving glaciers. Agricultural land is located east of Duck Mountain 8 and Riding Mountain 9 as well as between the two highlands 10. Northwest/southeast trending lines, particularly noticeable east of Duck Mountain, are Lake Agassiz strandlines 11.

Variation in the shades of blue in the water bodies is an indication of the amount of suspended sediment in the water. Where there is a lot of suspended sediment (usually in shallow lakes) the water is imaged as milky blue, but where there is little (usually in deep lakes) the water appears as dark blue; compare for example Whitewater Lake 12 with Clear Lake 13. Shallow lakes with large suspended sediment concentrations include Dauphin Lake 14, Lake Manitoba (both north 15 and south 16), Dog Lake 17, and Jackfish Lake 18. Intermediate (medium blue) are Lake St. Martin 19, Waterhen Lake 20, and Sturgeon Bay 21 off Lake Winnipeg. Lake Winnipegosis is mainly dark blue 22 indicating little suspended sediment, but two lighter patches, one off Red Deer Point 23 and one near Duck Bay 24, may be ice remnants. Perhaps the northern part of Lake Winnipegosis has only recently become clear of ice leaving little time for sediment to be stirred up.

Figure 2.3: Lakes of West Central Manitoba

Figure 2.3: Lakes of West Central Manitoba

Figure 2.3

LANDSAT image: May 16, 1973

Bands: 4 0.5-0.6 micrometres (green)

5 0.6-0.7 micrometres (red)

7 0.8-1.1 micrometres (infrared)

Scale: 1:1,000,000 (approx.)