Topography
- The Canadian Shield is more than 2 billion years old
- Consists of great volcanic mountains, which were leveled by millions of years of erosion
- It is the geographic foundation of Canada, and covers more than half of its' surface area
- It has a platform of rocks that extends from Labrador, around Hudson Bay and James Bay, in the east, south to the Great Lakes, and west to the Interior Plains
- During the Ice Age, glaciers removed most of the Shield's soil, leaving a barren rock surface in many places
- The retreat of glaciers affected the drainage of the Shield substantially
- Debris deposited by the glaciers dammed up rivers, or rerouted them to flow to different paths
- As a result, the Shield consists of a pattern of rivers, lakes, swamps and muskeg (level bogs/swamps found in Canada)
- The average elevation of the Canadian Shield is about 100m above sea level in the north, and rises to around 500m in the south
- The centre of the Shield is much lower in elevation than its' other portions
- The areas around Hudson Bay and James Bay are lowlands covered with clay. As a result, most rivers in the region flow into those two bays.
Vegetation
- Boreal forest covers most of the Canadian Shield
- Some deciduous trees, such as poplar and white birch, are also present. They are small and fragile, and thus are more suited to the pulp & paper industries than to lumbering
- North of the treeline, no trees can grow. The growing seasons are not long enough, there is little precipitation, and there is permafrost
Climate
- The climate varies throughout the vast area
- The north have longer and colder winters, and as a result have shorter, cooler summers
- Throughout the entire region, temperatures in the winter usually go below -10 C, and as low as -30 at times
- In summer months, it could get as warm as 20 C
Economic Activity
- Resources the Shield produces include fur, minerals, and hydro electricity, and other industries include forestry and tourism
- The Shield is filled with deposits of nickel, budder, silver, and copper
Environmental Concerns
- Acid rain is an issue in the Canadian Shield
- Caused by pollution from cars and factories
- Acid rain damages aquatic life, forests, crops, and buildings
- Sources of acidic emissions include coal-powered electric plants, industrial boilers, metal smelters, vehicles and trucks