Law of Superposition – Determining the relative ages of undisturbed sedimentary rocks
A fundamental principle of geology, The Law of Superposition stipulates that sedimentary rocks that are not in any way disturbed will have the oldest and most recent layers at the bottom. This principle is used to calculate the relative ages for the undisturbed sedimentary rocks sequence (James 2017). The law of superposition is used by geologists to calculate the relative ages for the undisturbed series of sedimentary stones. It states that sedimentary rocks have the oldest and youngest layers at the bottom of an undisturbed sequence. You can see this principle in outcrops. Outcrops show that the oldest and youngest rocks are visible at the bottom while those at the top are the youngest. Other relative dating methods, such as inclusions and cross-cutting relationships or fossil correlation, can be used by geologists to establish the rock’s relative age. Geologists must identify both the oldest and youngest layers of rock at the bottom to apply superposition in order to calculate the relative ages for the undisturbed sedimentary rock sequence (James 2017, 2017).