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Table of Contents
Foreword
Preface
Glossary

Chapter 1: Introduction

1.16: Transect Across the Assiniboine Valley North of Miniota

This stereo triplet transect across the Assiniboine Valley shows the standard 60 percent overlap: A15528:44 (centre photo) overlaps A15528:43 (right photo) by 60 percent, and A15528:45 (left photo) overlaps A15528:44 by 60 percent. So each part of the earth’s surface is shown on two photos (stereopairs) thus enabling stereoscopic viewing. Dashed lines on figure 1.16b bound the Assiniboine Spillway 1 that carried water from glacial lakes in Saskatchewan to glacial Lake Agassiz in Manitoba . The spillway occupies the centre of the area, with the south flowing Assiniboine River 2 on its floor. At least five cut offs can be seen 3. The spillway has steep sides, both on the east 4 and west 5, but two creek valleys 6 dissect the west wall.

These photos also illustrate the use of photo interpretation criteria: tone, texture, pattern and shape.

Tone: the sediment-laden Assiniboine River has a light-grey tone 7 whereas a prominent cut off in the north 8 is dark-toned because it carries no suspended sediment. Numerous sloughs east and west of the spillway 9 are dark-toned for the same reason.

Texture: the water surfaces are mainly smooth textured 10; whereas the valley walls, especially the east wall 11, have a mottled texture.

Pattern: elements of the checkerboard pattern of the DLS are seen in the east 12 and west 13.

Shape: the river displays the distinctive meandering form 14 with crescent-shaped cut offs 15. Curved meander scrolls 16 indicate previous positions of the river.

Figure 1.16.a: Transect Across the Assiniboine Valley North of Miniota

Figure 1.16.a: Transect Across the Assiniboine Valley North of Miniota

Figure 1.16

Vertical air photos: A15528-43, 44,45

Flight height: 20,000 feet a.s.l.; lens focal length: 6 inches

Scale: 1:37,300 (approx.)

Date: October 7, 1956

Location: Townships 13 and 14, Ranges 26 and 27 WI

Map sheets: 1:250,000 62K Riding Mountain

1:50,000 62K/3 Miniota


Figure 1.16.b: Transect Across the Assiniboine Valley North of Miniota

Figure 1.16.b: Transect Across the Assiniboine Valley North of Miniota


Figure 1.16.c: Transect Across the Assiniboine Valley North of Miniota

Figure 1.16.c: Transect Across the Assiniboine Valley North of Miniota