Relative age dating also means paying attention to crosscutting relationships.
Say for example that a volcanic dike, or a fault, cuts across several sedimentary layers, or maybe through another volcanic rock type.
Like the other kind of dating, geologic dating isn’t always simple.
The half-life of carbon 14, for example, is 5,730 years.Pretty obvious that the dike came after the rocks it cuts through, right?With absolute age dating, you get a real age in actual years.Relative dating is used to arrange geological events, and the rocks they leave behind, in a sequence.The method of reading the order is called stratigraphy (layers of rock are called strata).
Throughout the history of life, different organisms have appeared, flourished and become extinct.