potassium-argon dating

[ puh-tas-ee-uh m-ahr-gon ]
/ pəˈtæs i əmˌɑr gɒn /

noun Geology.

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

British Dictionary definitions for potassium-argon dating

potassium-argon dating


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

Science definitions for potassium-argon dating

potassium-argon dating

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.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.