How has glaciation affected the physical geography of the united states and canada?
The Canadian Shield and the Great lakes were formed by glaciers. Canada was nearly completely covered by ice, as well as the northern part of the USA, both blanketed by the huge Laurentide ice sheet. The current surface expression of the Shield is one of very thin soil lying on top of the bedrock, with many bare outcrops. This arrangement was caused by severe glaciation during the last ice age, which covered the Shield and scraped the rock clean. The Shield is one of the world’s richest areas in terms of mineral ores. It is filled with substantial deposits of nickel, gold, silver, and copper. Throughout the Shield there are many mining towns extracting these minerals. The Canadian Shield — also called the Laurentian Plateau, is a massive geological shield covered by a thin layer of soil that forms the nucleus of the North American or Laurentia 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,
