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Canada's three highland areas lie north, east and west of the sheild and lowland areas. Each one is different as they each are formed diffently and have different pasts
1. Appalachian Mountains
This mountain belt strectes from the State of Georgia in the United States to Newfoundland in Canada. The Appalachian Mountains were formed approximately 300 m.y.a., near the end of the Paleozoic Era when the sedimentry rock layers were uplifted and folded. These mountains too were high and had jagged peaks, but erosion has reduced them to rolling mountains and hills.
Non-metallic material such as coal, asbestos and salt are found within the sedimentry layers of the Appalachians. Between mountains there are plateaus of igneous rock, where metallic minerals such as iron and zinc are mined.
2. The Innutian Mountains
In the Canada's far north, the Innutian Mountains stand like icy watch towers, and many of which are over 3 000 metres1 in height. These mountains were constructed during the Mesozoic Era. They are much younger than the Appalachians, and the erosion has not yet have had effect on these mountains. These mountains support no vegetation since they are in the frozen.
3. Western Cordillera
The western cordillera, a combination of various structures stand along the western edge of Canada. It consists of mountains after mountains seprated by plateus and valleys. Interestingly these mountains contain the only remaining glaciers other than the Artic.
a) The Rocky Mountains
The Rocky Mountains on the eastern most side of the Western Cordillera is made of folded sedimentry rock. These rocks contains many fossils from ancient seas. These proves that this part of Canada was once submerged in water. Millions of years later great forces inside the earth forced this bedrock up.
Soaring high, these mountains are very difficult to cross today, as it was in the past.
The rocky mountain trench divides the rocky mountains from the next series of mountain ranges on the west. This valley was formed by faulting.
b) Interior Plateaus and Mountain Ranges
In the centre of western cordillera is a series of mountain ranges and plateaus. Although not as high as the rockies, these mountain ranges pose a challenge to cross. Many of the Interior plateaus are formed by volcanic activity.
c) The Coast Mountains
The Coast mountains are a range of mountains made of igneous rock. These esxtend along the western most part of the cordillera. These also form the islands found off the coast of British Columbia. Canada's highest peak, Mount Loagan2 is a part of this range.
Pictures: Top Right- Appalachian Mountains; Middle Left- A river valley in the Western Cordillera; Bottom- Cutaway of the Western Cordillera.
1; 2 Canada- Land of Diversity
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