This geologic map is showing the varying age of bedrock underlying North America. Time scale for North America terrain is indicated by different colors. From most recent to oldest, age is indicated by: yellow, green, blue, red. This combination reveals the geologic history of North America through the interrelation of rock type, topography and time.
This is a map of North America craton. The brown area shows the part of the North American continent that has been stable for over 600 million years. The green area on the illustration shows new continental material that was added relatively recently, within the last 600 million years. The purple area fringing the stable continental core is made up of older Precambrian basement that was deformed during plate collisions that occurred within the last 600 million years.
This is a map showing the world geologic provinces.