The effects of dissolved salts on oxygen and hydrogen isotope fractionation between water vapor and brines at 50--100 degrees C
A series of vapor-liquid water equilibration experiments were carried out in order to determine the effects of dissolved salts (NaCl, KCl, MgCl{sub 2}, CaCl{sub 2}, MgSO{sub 4}, Na{sub 2}SO{sub 4}, and their mixtures) on oxygen and hydrogen isotope activity ratios in brines at 50--100{degrees}C. NaCl, KCl and Na{sub 2}SO{sub 4} have little or no effect on oxygen isotope activity ratios. However, oxygen isotope activity ratios in CaCl{sub 2}, MgCl{sub 2}, and MgSO{sub 4} solutions are significantly lower than their concentration ratios. In all of the salt solutions studied, hydrogen isotope activity ratios are appreciably higher than their concentration ratios. The isotope effects are all linear with the molalities of the solutions. Mixed salt solutions, including those mimicking natural brines, exhibit the isotope effects additive of those of individual salts. The isotope salt effects observed in this study have profound implications to isotope geochemistry.
- Research Organization:
- Oak Ridge National Lab., TN (United States)
- Sponsoring Organization:
- USDOE; USDOE, Washington, DC (United States)
- DOE Contract Number:
- AC05-84OR21400
- OSTI ID:
- 5598334
- Report Number(s):
- CONF-920761-8; ON: DE92010432
- Resource Relation:
- Conference: 7. water-rock interaction conference, Park City, UT (United States), 9-23 Jul 1992
- Country of Publication:
- United States
- Language:
- English
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