自从1966年Loosli&Oeschchger测定出大气中的81Kr,就已经有人设想放射性81Kr(半衰期为(2.29±0.11)×105年)可能成为测定古老地下水年龄(105~106年)的有效工具。但一直没有付诸实践,直到2000年,Collon等人首次利用81Kr同位素确定澳大利亚大自流盆地(GAB)的古老地下水年龄。本篇文章中主要介绍了影响81Kr同位素测年的因素,81Kr的取样制样分析过程,回旋加速质谱仪分析81Kr同位素的原理。 Since Loosli & Oeschchger measured 81Kr in the atmosphere in 1966, it has been assumed that a radioactivity of 81Kr (2.29 ± 0.11 × 105 years) may be an effective tool for determining the age of ancient groundwaters (105-106 years). However, it has not been put into practice until the year 2000. For the first time, Collon et al. Used 81Kr isotopes to determine the age of ancient groundwater in the Gobi Basin in Australia. This article mainly introduces the factors affecting 81Kr isotope dating, 81Kr sampling sample preparation process, and the cyclotron mass spectrometer to analyze the principle of 81Kr isotope.