The Grand Canyon Continued
Erosion takes a long time to turn a desert floor into a Grand Canyon. Some scientists believe it took as long as six million years. Others believe it was much faster, taking only one million years. Either way, it was a long time!
Different types of rocks form the Earth. In the Grand Canyon, each layer can be seen. The strata (several layers, one atop the other) are more clearly displayed here than anywhere else on Earth. Scientists can get a clear picture of each layer. These layers of rock rise one full mile above the Colorado River.