canadian shield

The Canadian Shield — also called the Precambrian Shield, Laurentian Shield, Laurentian Plateau, or Bouclier Canadien (French) — is a large  shield covered by a thin layer of soil that forms the nucleus of the North American craton. It has a deep, common, joined bedrock region in eastern and central Canada and stretches North from the Great Lakes to the Arctic Ocean, covering half the country. It also includes most of Greenland and extends into the United States as the Adirondack Mountains and the Northern Highland. The Canadian Shield is U-shape, but almost circular, which gives it an appearance of a warrior's shield or a giant horseshoe, and is a subsection of the Laurentia craton signifying the area of greatest glacial impact (scraping down to bare rock) creating the thin soils.
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