The layers are different colors, including pink, gray, white, vermilion, and chocolate, representing different rock types and ages.

Sediments
Sedimentary rocks are made up of rock fragments. These fragments come from other rocks that have been broken down by the weather over thousands of years. Removed by wind, water or ice (a process known as erosion), the fragments may settle on a stream bed, say, or at the bottom of the sea. They are called sediments. Sand, silt, gravel, mud, even the remains of living creatures, are all kinds of sediments. If they lie undisturbed for a few million years, the grains will cement together to form rocks. Sandstone, shale and limestone are all sedimentary rocks.