Radiometric dating relies on the constant rate of decay of
The atoms of some chemical elements have different forms, called isotopes.These break down over time in a process scientists call radioactive decay.Each original isotope, called the parent, gradually decays to form a new isotope, called the daughter.Each isotope is identified with what is called a ‘mass number’.Using relative dating the fossil is compared to something for which an age is already known.
But, how can we determine how old a rock formation is, if it hasn’t previously been dated?
Then the computed age based on the accumulation of daughter products will be incorrect (Stasson 1998).
In order to use the valuable information provided by radiometric dating, a new method had to be created that would determine an accurate date and validate the assumptions of radiometric dating. Isotope dating satisfies this requirement, as daughter products do not decay back to the original parent element.
This amount is often unknown and is one of the downfalls of conventional radiometric dating.
However, isochron dating bypasses this assumption, as explained below. The final condition is the number of atoms of parent and daughter isotopes remaining in the rock and can easily be measured in a lab.