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Chapter 3: Geologic Structure and Landforms

3.90: Relict Ice Scour Features Near St. Laurent

In this flat area numerous intersecting lineations, trending in several directions, can be seen. Many are straight 1, but a few have a definite curve 2. Without the benefit of stereovision it is hard to tell whether they are negative or positive features. However, the fact that they are mainly dark-toned 3 due to high soil moisture content suggests that they are furrows. Also, in many cases the availability of water results in tree growth—dark-toned 4. These are minor relief features only a meter (3 ft) or so in depth, and it is suggested that they were scraped into the bottom of Lake Agassiz by the submerged parts of icebergs which must have been driven by winds from several different directions.

PTH 6 5 crosses the southwest corner with another road joining it from the east 6. The CN railway line 7 is north of, and parallel to, PTH 6. A minor track can be seen in the north 8. Several linear features defy explanation: some southwest/northeast trending lines demarcate areas of different tone 9; also a square feature may be a partially cut field of hay 10.

Figure 3.90: Relict Ice Scour Features Near St. Laurent

Figure 3.90: Relict Ice Scour Features Near St. Laurent


Figure 3.90

Vertical air photograph: A17529-208

Flight height: 8,800 feet a.s.l.; lens focal length: 153.04 mm

Scale 1:16,000 (approx.)

Date: July 27, 1961

Location: Township 17; Range 4WI

Map sheets: 1:250,000 62I Selkirk

1:50,000 62I/5 St. Laurent