Prehistoric Great Lakes explores the geological formation of the Great Lakes region and the bountiful natural resources which have shaped human history. Travel through time from the Precambrian bedrock of the Lake Superior region, laden with copper and iron-to limestone deposits rich with fossils from ancient seas-to a legacy coal and oil from lush and tropical swamps. Discover how the collision of continents, the power of glaciers and the persistence of life in an ever-changing environment shaped the Great Lakes region.