as blue. Living vegetation appears green, wheat field stubble as yellow and
autumn woods as red-brown. The scene is typical of the semi-arid zone which
constitutes the Great Plain of central Canada. The area represented by the
image is underlain by gently dipping sandstones, clays and shales of
Cretaceous age. The wooded Cyprus Hills, which barely extend into the south
east quadrant of the image, are composed of sands and gravels, and rise 500 m
above the general level of the plain. Hummocky moraine is a typical feature
of the landscape, but is not recognized here. The South Saskatchewan river
flows across the centre of the image area. The many anomalous pale blue
lakes, often with white fringes, are salt encrusted alkali flats. There are
3 principal forms of land use. The many anomalous pale blue lakes, often
with white fringes, are salt encrusted alkali flats. There are 3 principal
forms of land use. The presence of a field pattern defines areas of crop
production, predominantly wheat. Ranching areas are located about the Cypress
Hills and other non-agricultural areas. The uncultivated area occupying most
of the northeastern quadrant of the image is a military training site.
Figure 9. Akimiski Island, Ontario. 1447-15534-4,5,7. 13th October 1973.
The image is of a part of the Hudson Bay Lowlands along the western edge
of James Bay. The landscape is a low lying swampy plain with numerous lakes
and streams. Flat dipping Ordovician and Silurian sediments, mostly dolomite
limestone, shale and sandstone, underly the area. There are very few outcrops
because of a thick overburden of glacial material. A belt of raised beaches
can be seen to follow the coastline and circle Akimiski Island. The most
remarkable feature of the image is the complex circulation pattern formed by
the silt laden water. Large volumes of mud are deposited daily in the shallow
waters of the bay by the many streams and rivers. The circulation patterns
are due to the reworking of these soft bottom sediments by the action of wind
and currents.
