The rate of isotope decay is very consistent, and is not effected by environmental changes like heat, temperature, and pressure. This makes radiometric dating quite reliable.
Why is radiometric dating the most reliable method of dating?
Radiometric dating is a method used to date rocks and other objects based on the known decay rate of radioactive isotopes. The two uranium isotopes decay at different rates, and this helps make uranium-lead dating one of the most reliable methods because it provides a built-in cross-check.
Why is radioactive dating important in geological studies?
Geologists use radiometric dating to estimate how long ago rocks formed, and to infer the ages of fossils contained within those rocks. The universe is full of naturally occurring radioactive elements. Radioactive atoms are inherently unstable; over time, radioactive parent atoms decay into stable daughter atoms.