Radiometric dating (often called radioactive dating) is a technique used to date materials, based on a comparison between the observed abundance of particular naturally occurring radioactive
isotopes and their known decay rates. It is the principal source of information about the absolute age of rocks and other geological features, including the
age of the Earth itself. Among the best-known techniques are
potassium-argon dating and
uranium-lead dating. By allowing the establishment of geological timescales, it provides a significant source of information about the dates of
fossils and the deduced rates of
evolutionary change. Radiometric dating is also used to date
archaeological remains and ancient artifacts, the best known technique in this field being
radiocarbon dating.
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The process of using relative proportions of parent to daughter isotopes in radioactive decay to determine the age of a given rock or rock stratum.