Chapter 3: Geologic Structure and Landforms
Geologic interpretation of images begins with the identification of lineaments, “regional linear features caused by linear arrangement of regional morphological features such as streams, escarpments, and mountain ranges and tonal features that in many areas are the surface expressions of fractures or fault zones.”[i] The emphasis in this section is on geologic structures and landforms, both of which can be easily identified on air photographs and other images.
The sequence followed here is that often found in geomorphology books. Geologic structures and structurally controlled landforms are illustrated first, followed by images of mass wasting and of the results of the agents of erosion—running water, ground water, ice, wind and the sea. The meandering rivers of southern
3.2: Structures in the Precambrian Shield Northwest of Snow Lake
This area is located just west of that shown in figure 3.1. Two domes are located at 1 and 2, the latter being picked out by the shape of
Figure 3.2: Structures in the Precambrian Shield Northwest of Snow Lake
Vertical air photograph: A14982-49
Flight height: 30,000 feet a.s.l.: lens focal length: 152.91 mm
Date: June 14, 1955
Scale: 1:59,600 (approx.)
Location: Townships 69 and 70, Ranges 18 and 19 WI
Map sheets: 1:250,000 63K Cormorant
[i] Interpretation of the structure is from Mollard and Janes. op. cit., 24.