Radioactive dating how stuff works
This transformation may be accomplished in a number of different ways, including alpha decay (emission of alpha particles) and beta decay (electron emission, positron emission, or electron capture).
Another possibility is spontaneous fission into two or more nuclides.
Radioactive dating uses the decay rates of radioactive substances to measure absolute ages of rocks, minerals and carbon-based substances, according to How Stuff Works.
Scientists know how quickly radioactive isotopes decay into other elements over thousands, millions and even billions of years.
For most radioactive nuclides, the half-life depends solely on nuclear properties and is essentially a constant.In many cases, the daughter nuclide itself is radioactive, resulting in a decay chain, eventually ending with the formation of a stable (nonradioactive) daughter nuclide; each step in such a chain is characterized by a distinct half-life.In these cases, usually the half-life of interest in radiometric dating is the longest one in the chain, which is the rate-limiting factor in the ultimate transformation of the radioactive nuclide into its stable daughter.By allowing the establishment of geological timescales, it provides a significant source of information about the ages of fossils and the deduced rates of evolutionary change.Radiometric dating is also used to date archaeological materials, including ancient artifacts.