A simple gas analytical technique for the Dickson-type hydrothermal apparatus and its application to the calibration of MH, NNO and FMQ oxygen buffers
1984 年 18 巻 1 号 p. 19-29
詳細
1984 年 18 巻 1 号 p. 19-29
A simple gas chromatographic technique was developed for the determination of dissolved gases in the aqueous samples taken out from Dickson-type hydrothermal apparatus, and H2 concentration was measured at temperatures below 500°C and pressures below 1, 000 bars in aqueous systems containing magnetite-hematite, Ni-NiO and fayalite-magnetite-quartz oxygen buffers. Oxygen-fugacity ratios between buffers A and B can be obtained by using a relation: fO2 (A)/fO2 (B) = [CH2 (B)/CH2 (A)]2, where CH2 (A) and CH2 (B) are equilibrium H2 concentrations in the systems A-water and B-water under the same P-T condition. Using a few fO2 ratios thus obtained, corrections were evaluated for the fO2–T relationships of the buffers given by a thermochemical compilation of ROBIE et al. (1979).
