Abstract: While testing capability of mass spectrometer has been improved, sample fusion system becomes the main factor to effect Ar isotopes determination. Sample tube has been reconstructed from mono tube to multiple tube. After reconstruction, it allowes us to remove atmosphere Ar and measure hot blank beforehand. This reduces the influence of non radiogenic Ar to measuring results,which plays an important role especially to young volcanic rocks. Moreover, measuring time is saving. The second change that has made is quartz tube from cylinder shape to three pinstripe. Quartz material contacted to the molybdenum crucible reduces to one fifth. This makes hot blank even lower and the removal time is shorter. After modification of sample tube, the content of radiogenic Ar increases and reproducibility and accuracy of standards is better.

Key words: Ar isotope, sample tube, modification

摘要： 随着质谱仪性能的改进，熔样系统成为影响Ar同位素分析精度的主要因素。将原来的单进样管改造成为多进样管，可以预先去气和测量热空白值，降低了非放射成因氩对测试结果的影响，这对于年轻火山岩的定年尤为重要；1/5，进一步降低了热空白并减少了去气时间。通过对样品管的改造，提高了样品测试中放射成因氩的含量，标样多次测试结果具有很好的重现性和准确度。

关键词: 氩同位素, 样品管, 改造