High-precision carbon and oxygen stable isotope microanalysis by integrating IRMS with the MICAL and laser ablation techniques

Abstract

Isotope Ratio Mass Spectrometry (IRMS) is a gas mass spectrometric technique capable of achieving highly precise and accurate measurements of isotopic ratios in light elements. It has been extensively utilized for over half a century. The ultra-micro analytical method for carbonate stable isotopes (MICAL-CF-IRMS), developed by Ishimura et al. (2004, 2008), enables high-precision analyses using only one-hundredth of the sample quantity required in conventional techniques. However, its sample introduction system imposes a limitation on spatial resolution. Laser Ablation (LA), in contrast, allows for the high spatial resolution sampling under atmospheric pressure. To achieve a high-precision carbon and oxygen stable isotope analysis of ultra-micro carbonate samples at high resolution, we have developed an integrated analytical system of both IRMS and LA techniques.