K–Ar dating

Radiometric dating method

Potassium–argon dating, abbreviated K–Ar dating, is a radiometric dating method used in geochronology and archaeology. It is based on the measurement of the product of the radioactive decay of an isotope of potassium (K) into argon (Ar). Potassium is a common element in many materials, such as feldspars, micas, clay minerals, tephra, and evaporites.

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