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Chapter 3: Geologic Structure and Landforms

3.1: Structures in the Precambrian Shield Near Snow Lake

This area is located within the Churchill Province of the Precambrian Shield, north of Snow Lake. Compton Lake 1 is located in the northwest, branches of Squall Lake 2 and McLeod Lake 3 are located in the southwest, Angus Bay 4 off Herblet Lake and Wolverton Lake 5 are located in the southeast, Stack Lake 6 is located in the northeast, and Zoratti Lake 7 in the north. The rocks in this area “can be considered for simplicity, as banded gneiss in its many forms.”[i]. Gneiss is a metamorphic rock formed by compressing and heating of the pre-existing rocks. Tectonic activity has produced a series of folds, and differential weathering and erosion of the rock layers of varying resistance has resulted in ridges and valleys that reflect the structure. A dome can be recognized at 8 and an auticline (up fold) at 9. “The lighter grey-toned irregularly shaped rock body at 10 is probably a lens of pegmatite.”[ii] The shapes of some of the lakes, especially Wolverton Lake 5 and Zoratti Lake 7, are clearly influenced by the structure.

Figure 3.1: Structures in the Precambrian Shield Near Snow Lake

Figure 3.1: Structures in the Precambrian Shield Near Snow Lake

Figure 3.1

Vertical air photograph: A14982-52

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

Date: June 14, 1955

Scale: 1:59,500 (approx.)

Location: Townships 69 and 70, Ranges 16, 17 and 18WI

Map Sheets: 1:250,000 63J Wekusko Lake

63K Cormorant Lake

63N Kississing Lake

63O Nelson House


[i] Mollard, J. D. and Janes, J. R. Air Photo Interpretation and the Canadian Landscape. Ottawa: Energy Mines and Resources Canada, 1984, 22.

[ii] Mollard and Janes, op. cit. 24.