Canadian Shield

The Canadian Shield is also called the Laurentian Plateau, or "" (French).
It is a large area of exposed Precambrian igneous and high-grade metamorphic rocks (geological shield). It is the ancient geological core of the North American continent (the North American Craton or Laurentia). 
A continuation of the shield is in west Greenland, to which it was once connected. In the United States the shield is mostly covered with much younger rocks and sediment.
The Canadian Shield round Hudson Bay is covered with shallow soil. Its main industrial use is for mining.