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Table of Contents
Foreword
Preface
Glossary

Chapter 3: Geologic Structure and Landforms

3.6: Fault Scarp on the Precambrian Shield Northwest of Wabowden

The rocks in this part of the shield are mapped as “highly metamorphosed and partly migmatic derivative”,[i] but, as in the case of figure 3.4, they are mainly covered by surficial material. A striking linear feature trending north-northeast to south-southwest with a 26-degree bend at its southern end breaks the monotony of the topography 1. This is interpreted as a “fault scarp, post glacial”[ii] with the downthrow side to the southeast. The feature peters out in the south, but two other linear features at 2 and 3 seem to be a continuation of the same structure. A small meandering stream developed on the surficial material that offers uniform resistance to erosion crosses the area from north-northwest to south-southeast 4. In the southwest are extensive areas of string bog 5—strips of vegetation separated by water—that are perpendicular to the general slope of the land to the southeast. The string bog surrounds lenses of highland covered by coniferous trees 6. Streamers of light tone at the southern ends of the lenses 7 indicate slow movement of land to the southeast.

Figure 3.6: Fault Scarp on the Precambrian Shield Northwest of Wabowden

Figure 3.6: Fault Scarp on the Precambrian Shield Northwest of Wabowden

Figure 3.6

Vertical air photograph: A14982-154

Flight height: 30,000 feet a.s.l.; lens focal length: 152.91 mm

Date: June 14, 1955

Scale: 1:58,000 (approx.)

Location: Township 70, Ranges 11 and 12 WI (southern two thirds of photo)

Map sheets: 1:250,000 630 Nelson House

1:50,000 630/3 McNeill Lake

Notes

[i] Geological Highway Map of Manitoba. 1994.

[ii] Bostock, H. S. A Catalogue of Selected Airphotographs. Ottawa: Geological Survey of Canada, Paper 67-48, 1968, 66.