Diffusion measurements and the potassium argon method of dating Gigolo chatline
And OE Christians (theistic evolutionists) see no problem with this dating whilst still accepting biblical creation, see Radiometric Dating - A Christian Perspective.This is the crucial point: it is claimed by some that an old earth supports evolutionary theory and by implication removes the need for biblical creation.In other words, half of the radioactive isotope in a sample would have decayed to Nitrogen-14 (N-14) in just 5,730 years.C-14 dating of carbon-bearing materials is therefore limited to roughly 50,000 years.
But assuming the earth was formed at the time of the rest of our solar system, then recovered moon rock and meteorites can also be used to estimate the age of the earth.
Radioactive parent (P) atoms decay to stable daughter (D) atoms e.g.
the carbon isotope C-14 decays to nitrogen-14 and the uranium isotope U-235 decays to the lead isotope Pb-207.
This implies the earth is at least 20 million years old.
Astronomical cycles can also be used to measure relative age.