Relative dating determines the relative age of rock layers according to their relative depth. However, radiometric dating determines the absolute age with the use of decaying products of the natural radioactive isotopes.

What is the purpose of relative dating?

Relative dating puts geologic events in chronological order without requiring that a specific numerical age be assigned to each event. Second, it is possible to determine the numerical age for fossils or earth materials.

What is relative and radiometric dating?

Relative dating is used to determine a fossils approximate age by comparing it to similar rocks and fossils of known ages. Absolute dating is used to determine a precise age of a fossil by using radiometric dating to measure the decay of isotopes, either within the fossil or more often the rocks associated with it.