Write this in your own words The Canadian Shield is U-shaped and is a subsection of the Laurentia craton signifying the area of greatest glacial impact (scraping down to bare rock) creating the thin soils. The Canadian Shield is more than 3.96 billion years old.
North of the Us, Canada, has a 3.96 billion year old U-shaped subsection named The Canadian Shield. The Canadian Shield signifies the greatest glacial impact, or scraping down to bare rock.
