a method for estimating the age of a mineral or rock, based on measurement of the rate of decay of radioactive potassium into argon.
Origin of potassium-argon dating
First recorded in 1965–70
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
a technique for determining the age of minerals based on the occurrence in natural potassium of a small fixed amount of radioisotope 40 K that decays to the stable argon isotope 40 Ar with a half-life of 1.28 × 10 9 years. Measurement of the ratio of these isotopes thus gives the age of the mineralCompare radiocarbon dating, rubidium-strontium dating
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
A method of radiometric dating, involving analysis of the ratio of potassium 40 (a radioactive isotope of potassium) to argon (the product of radioactive decay of potassium 40) in a given sample.
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