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Table of Contents
Foreword
Preface
Glossary

Chapter 3: Geologic Structure and Landforms

3.22: Rain Splash, Rill and Gully Erosion South of the Assiniboine River, South of Lavenham

The eastward flowing Assiniboine River 1 clips the northern edge of the photo. In this area the Assiniboine River is etched into the Assiniboine Delta that is composed of sands. The meandering river shows the characteristic river cliff 2 on the outside of the bend with a grass and willow covered point bar 3 on the inside of the bend. Most of the land has been cleared for agriculture with the exception of a block of deciduous woodland in the north 4 and strips of woodland along creek channels 5. The cleared land displays the mottled tones 6 characteristic of sandy soils. Rain splash erosion results in light tones on slightly elevated areas 7. In other areas erosion is concentrated along minor rills 8. Some of these 9 lead towards a larger gully 10 that combines with another gully from the south 11 before reaching the Assiniboine. Water from these gullies has deposited a small delta 12 into the Assiniboine. Rather surprisingly the gullies are most obvious where they cut across wooded land 13. In two cases gullies are retreating from wooded areas into agricultural land by a process of headward erosion with a steep head wall 14 at the point of maximum extent.

Figure 3.22: Rain Splash, Rill and Gully Erosion South of the Assiniboine River, South of Lavenham

Figure 3.22: Rain Splash, Rill and Gully Erosion South of the Assiniboine River, South of Lavenham

Figure 3.22

Vertical air photograph: A16621-79

Flight height: 9000 feet a.s.l.; lens focal length: 6 inches

Scale 1:16,200 (approx.)

Date: July 18, 1959

Location: Township 9; Range 10WI

Map sheets: 1:250,000 62G Brandon

1:50,000 62G/10 Treherne