Oxygen Isotope Analysis of Fluid Inclusions in Speleothems

Abstract

A bromine pentafluoride line was built for water samples after O'Neil and Epstein (1966). The line is used to decompose water to produce oxygen gas by reacting with bromine pentafluoride and subsequently to convert the oxygen gas to carbon dioxide gas for oxygen isotope analysis. It was applied to water samples from fluid inclusions in speleothems. Water was extracted from speleothems by crushing them in a stainless steel tube in a manner initially developed by Roedder et al. (1963).
The precisions of the bromine pentafluoride line for standard water samples, VSMOW and NBS-1, were ±0.15 and ±0.20‰, respectively. The precision for the whole analytical procedure including the step of crushing speleothems was checked using natural flowstone samples from Bermuda and was found to be ±0.24‰.