Comparison of water isotope analysis between cavity ring-down spectroscopy and isotope ratio mass spectrometry

Abstract

δD and δ18O of natural waters with δ18O ranging from -24 to -6‰ were measured using a cavity ring-down spectroscopy (CRDS) in order to confirm that the CRDS method can be an alternative to conventional isotope ratio mass spectrometry (IRMS). The deviations of δD and δ18O values obtained using the CRDS and IRMS methods are less than 0.8‰ and 0.3‰, respectively, which are practically sufficient for geochemical/environmental researches of natural waters, indicating that the CRDS method can be an alternative to the IRMS methods for environmental liquid water samples.