Before revision: 250px|The Permian through Jurassic stratigraphy of the Colorado Plateau area of southeastern Utah is a great example of Original Horizontality and the Law of Superposition, two important ideas used in relative dating.
After revision: 250px|The Permian through Jurassic stratigraphy of the Colorado Plateau area of southeastern Utah is a great example of Original Horizontality and the Law of Superposition, two key principles used in relative dating.