Absolute dating science
We define the rate of this radioactive decay in half-lives.
If a radioactive isotope is said to have a half-life of 5,000 years that means after 5,000 years exactly half of it will have decayed from the parent isotope into the daughter isotopes.
These isotopes break down at a constant rate over time through radioactive decay.
The majority of the time fossils are dated using relative dating techniques.The Wheeler Formation has been previously dated to approximately 507 million year old, so we know the trilobite is also about 507 million years old.But, how can we determine how old a rock formation is, if it hasn’t previously been dated? There are two main methods determining a fossils age, relative dating and absolute dating.
Relative dating is used to determine a fossils approximate age by comparing it to similar rocks and fossils of known ages.
Using relative dating the fossil is compared to something for which an age is already known.