Liquid-vapor fractionation of oxygen and hydrogen isotopes of water from the freezing to the critical temperature

Journal Article · Mon Aug 01 04:00:00 UTC 1994 · Geochimica et Cosmochimica Acta; (United States)

DOI:https://doi.org/10.1016/0016-7037(94)90096-5· OSTI ID:6759133

Horita, J; Wesolowski, D J ^[1]

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1. Oak Ridge National Lab., TN (United States)

The equilibrium fractionation factors of oxygen and hydrogen isotopes between liquid water and water vapor have been precisely determined from 25 to 350[degrees]C on the VSMOW-SLAP scale, using three different types of apparatus with static or dynamic techniques for the sampling of water vapor. The results for both oxygen and hydrogen isotope fractionation factors between 25 and 100[degrees]C are in excellent agreement with the literature. The results for the hydrogen isotope fractionation factor above 100[degrees]C also agree quantitatively with the literature values of Merlivat et al. (1963) and Bottinga (1968). The results for the hydrogen isotope fractionation factor obtained in this study and from most of the literature was regressed to the equation, 10[sup 3] ln [alpha][sub 1-v](D) = 1158.8(T[sup 3]/10[sup 9]) - 1620.1(T[sup 2]/10[sup 6]) + 794.84(T/10[sup 3]) - 161.04 + 2.9992(10[sup 9]/T[sup 3]), from 0[degrees]C to the critical temperature of water (374.1[degrees]C) within [+-]1.2(1[sigma]) (n = 157); T(K). The crossover temperature is 229 [+-] 13[degrees]C 1[sigma]. The values for the oxygen isotope fractionation factor between liquid water and water vapor are, however, at notable variance with the only dataset available above 100[degrees]C in the literature, which is systematically higher (av. + 0.15 in 10[sup 3] in [alpha][sub l-v] ([sup 18]O)) with large errors ([+-]0.23 in 1[sigma]). The results and most of the literature data below 100[degrees]C were regressed to the equation, 10[sup 3] ln [alpha][sub l-v]([sup 18]O) = -7.685 + 6.7123(10[sup 3]/T) - 1.6664(10[sup 6]/T[sup 2])+0.30541(10[sup 9]/T[sup 3]), from 0 to 374.1[degrees]C within [+-]0.11 (1[sigma]) (n = 112); T(K). A third water-steam isotope geothermometer, using the ratio of [Delta][delta]D/[Delta][delta][sup 18]O given by water and steam samples, is readily obtained from the above equations.

• DOE Contract Number: AC05-84OR21400
• OSTI ID: 6759133
• Journal Information: Geochimica et Cosmochimica Acta; (United States), Journal Name: Geochimica et Cosmochimica Acta; (United States) Vol. 58:16; ISSN GCACAK; ISSN 0016-7037
• Country of Publication: United States
• Language: English

Related Subjects

54 ENVIRONMENTAL SCIENCES
540310* -- Environment
Aquatic-- Basic Studies-- (1990-)
FLUIDS
FUNCTIONS
GASES
HYDROGEN COMPOUNDS
HYDROGEN ISOTOPES
ISOTOPE APPLICATIONS
ISOTOPE RATIO
ISOTOPES
OXYGEN COMPOUNDS
OXYGEN ISOTOPES
PARTITION FUNCTIONS
PHASE TRANSFORMATIONS
STABLE ISOTOPES
SURFACE WATERS
TRACER TECHNIQUES
VAPORS
WATER
WATER VAPOR