Host: Abstracts of Annual Meeting of the Geochemical Society of Japan
Name : Abstracts of Annual Meeting of the Geochemical Society of Japan
Number : 68
Date : September 01, 2021 - September 15, 2021
Pages 148-
We have developed an in-situ uranium–thorium (238U–230Th) and uranium–protactinium (235U–231Pa) dating methods using multiple-spot femtosecond laser ablation-ICP-triple quadrupole-mass spectrometry (msfsLA-ICP-TQ-MS) for rapid age determinations of quaternary volcanic ash samples. In previous studies, in situ analysis of 230Th and 231Pa have been conducted by high-resolution sector field mass spectrometry, especially secondary ionization mass spectrometry (SIMS). However, SIMS requires a long-time measurement (10 minutes per sample). Because of this drawback, SIMS is not suitable for collection of chronological big data. In this study, msfsLA and ICP-TQ-MS were combined for the short-time measurement of 230Th and 231Pa (1 minute per sample). In the presentation, analytical accuracy and precision, and time required for measurements will be evaluated and the developed method will be applied to age determination of quaternary volcanic ash samples.
