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Table of Contents
Foreword
Preface
Glossary

Chapter 1: Introduction

1.10: Air Photo Interpretation Criteria Applied to an Area on the Assiniboine River South of Long Plain First Nation

The Assiniboine River 1 flows from west to east and then turns north. The photo illustrates the use of the criterion, tone, in interpretation of landforms. The tone of the river is light grey 2 indicating high suspended sediment content; at several locations in the channel very light-toned areas 3 are sandbars. South of the west-east river section and west of the south-north section are linear dark-toned features 4 and 5. These are meander scrolls left as relics of former positions on the river as it migrated north and east. Southeast of the river is a field in which the tone varies from very light 6 to very dark 7, a reflection of water content of the soil; dark grey indicates high water content, and light grey suggests low water content. This type of variation is characteristic of sandy soils.  Dark-toned, rough-textured areas 8 cover much of the photo. These are areas of deciduous woodland, an interpretation supported by rounded shadows 9 thrown by the trees near clearings.

Figure 1.10: Air Photo Interpretation Criteria Applied to an Area on the Assiniboine River South of Long Plain First Nation

Figure 1.10: Air Photo Interpretation Criteria Applied to an Area on the Assiniboine River South of Long Plain First Nation

Figure 1.10

Vertical air photo: A16574-44

Flight height: 8,800 feet a.s.l.; lens focal length: 6 inches

Scale: 1:15,100 (approx.)

Date: June 19, 1959

Location: Township 9, Range 8 WI

Map sheets: 1:250,000: 62G Brandon

1:50,000: 62G/16 Portage la Prairie