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Table of Contents
Foreword
Preface
Glossary

Chapter 3: Geologic Structure and Landforms

3.9: Escarpment North of Grand Rapids

In this area west of the north end of Lake Winnipeg, southwest of Buffalo Lake the junction between Ordovician rocks to the east and Silurian rocks to the west is marked by a prominent escarpment 1 with a major westward embayment 2. Water percolates down through the Silurian carbonate rocks to emanate from the base of the escarpment giving rise to a series of eastward flowing rivers 3. White patches 4 are probably sinkholes, whereas lakes 5 are dark in tone. Curvilinear lines along the face of the escarpment 6 mark former high levels of Lake Winnipeg, just off the photo to the east. Deciduous trees cover most of the area, and there is little obvious human impact except for a few forest trails, one of which follows the face of the escarpment 7.

Figure 3.9: Escarpment North of Grand Rapids

Figure 3.9: Escarpment North of Grand Rapids

Figure 3.9

Vertical air photo: A25997-198

Flight height: 9,920 feet a.s.l.; lens focal length: 152.034 mm

Date: June 25, 1982

Scale: 1:18,400 (approx.)

Location: Township 51, Range 13 WI

Map sheets: 1:250,000 63G Grand Rapids

1:50,000 63G/6 Eating Point