Relative dating uses to estimate how old a fossil is
For biological objects older than 50,000 years, scientists use radioactive dating to determine the age of rocks surrounding where the material was found.
As an example of how they are used, radiometric dates from geologically simple, fossiliferous Cretaceous rocks in western North America are compared to the geological time scale.
Scientists calculate ages by measuring how much of the isotope remains in the substance.
Continue Reading The key to an age of a substance is the decay-product ratio.
A common form of criticism is to cite geologically complicated situations where the application of radiometric dating is very challenging.
These are often characterised as the norm, rather than the exception.