The estimation of calibration curve considering the ion yields of each water molecule species in rhyolitic glass by secondary ion mass spectrometry

Abstract

To determine the water concentration in volcanic glass, secondary ion mass spectrometry is powerful. Using the ¹³³Cs⁺ beam, the data of the high-water content rhyolitic glasses deviate from the calibration line. However, the factor of shift is not well understood. In this study, we focus on the water species concentration using rhyolitic glass standards. For the calibration line by ¹H⁻/³⁰Si⁻ and OH content, the data do not deviate from the calibration line. But, the data of the standards H₂O_m dominant show the different trend from the calibration line. We evaluated the calibration curve assuming the ion yields of each water species are different and constant. These results reveal that the data deviate from the calibration line are caused by the different ion yields of each water species using ¹³³Cs⁺ beam.