The conventional procedure for analysis of 18O in aqueous solutions yield δ 18O values on an activity scale rather than a value for the isotope concentration. Conversion between the two scales in natural chloridic solutions containing magnesium, calcium and potassium is given by the equation (δ0 - δm)/(1000 + δm) × 103 = 1.11 MMg + 0.47 MCa - 0.16 MK, where δ0 is the δ value on a concentration scale, δm the measured activity delta and M the molality. This linear equation holds up to molalities of 6 in pure and mixed salt solutions. The correction is of significance for a variety of geochemical processes, among them the use of the isotope content of different brines as an indicator of the salinization mechanisms of water sources.
|Number of pages||7|
|Journal||Earth and Planetary Science Letters|
|State||Published - 1 Jan 1972|
ASJC Scopus subject areas
- Geochemistry and Petrology
- Earth and Planetary Sciences (miscellaneous)
- Space and Planetary Science