The effect of pressure on deuterium-hydrogen fractionation in high- temperature water

Science

Volumn 277, Issue 5327, 1997, Pages 791-794

  Driesner, T ^a,b  

^a ETH ZURICH   (Switzerland)

^b University of Tennessee Knoxville   (United States)

Author keywords

[No Author keywords available]

Indexed keywords

DEUTERIUM; MINERAL WATER; WATER;

ARTICLE; CALCULATION; FRACTIONATION; HIGH TEMPERATURE; MOLECULAR DYNAMICS; PRESSURE; PRIORITY JOURNAL; SIMULATION; SPECTROSCOPY;

EID: 0030860284     PISSN: 00368075     EISSN: None     Source Type: Journal    
DOI: 10.1126/science.277.5327.791     Document Type: Article

References (36)

1. H. Craig, in Nuclear Geology of Geothermal Areas (Consiglio Nazionale delle Ricerche, Pisa, Italy, 1963), p. 17. For reviews of the application of stable isotopes to the study of fluid-rock interaction, see Rev. Mineral. 16, 165 (1986).
2. H. Craig, in Nuclear Geology of Geothermal Areas (Consiglio Nazionale delle Ricerche, Pisa, Italy, 1963), p. 17. For reviews of the application of stable isotopes to the study of fluid-rock interaction, see Rev. Mineral. 16, 165 (1986).
3. 16O fractionation factors.
4. A-B is to leave out the symmetry number terms. For a detailed discussion, see V. I. Ferronsky and V. A. Polyakov, Environmental Isotopes in the Hydrosphere (Wiley, Chicester, UK, 1982), pp. 14-43.
5. A-B is to leave out the symmetry number terms. For a detailed discussion, see V. I. Ferronsky and V. A. Polyakov, Environmental Isotopes in the Hydrosphere (Wiley, Chicester, UK, 1982), pp. 14-43.
6. A-B is to leave out the symmetry number terms. For a detailed discussion, see V. I. Ferronsky and V. A. Polyakov, Environmental Isotopes in the Hydrosphere (Wiley, Chicester, UK, 1982), pp. 14-43.
7. V. B. Polyakov and N. N. Khariashina, Geochim. Cosmochim. Acta 58, 4739 (1994).
8. J. D. Frantz, J. Dubessy, B. Mysen, Chem. Geol. 106, 9 (1993).
9. W. Kohl, thesis, Univ. of Karlsruhe, Germany (1989).
10. H. A. Lindner, thesis, Univ. of Karlsruhe, Germany (1970).
11. C. I. Ratcliffe, D. E. Irish, J. Phys. Chem. 86, 4897 (1982).
12. D. L. Farber, Q. Williams, E. Knittle, Eos Trans. Am. Geophys. Union 71, 1600 (1990).
13. p and the ratio was set up in the order as given in Eq. 3.
14. -1 at 200 MPa. The bending and librational blueshifts used possibly overemphasize the contributions of these modes. Anharmonicity effects were not taken into account but - if important - are likely to reduce the contribution of the librational modes. In addition to the simple model of two stretching, one bending, and one librational mode, several other models with additional bands in all three regions were tested but gave very similar results. The qualitative picture shown in Fig. 1 is independent of the spectral model. Reducing the contributions from the bending and librational modes results in larger pressure effects at high temperature. Figure 1 is thus regarded as a conservative estimate of the magnitude of the pressure effects above the reference pressure.
15. -1 at 200 MPa. The bending and librational blueshifts used possibly overemphasize the contributions of these modes. Anharmonicity effects were not taken into account but - if important - are likely to reduce the contribution of the librational modes. In addition to the simple model of two stretching, one bending, and one librational mode, several other models with additional bands in all three regions were tested but gave very similar results. The qualitative picture shown in Fig. 1 is independent of the spectral model. Reducing the contributions from the bending and librational modes results in larger pressure effects at high temperature. Figure 1 is thus regarded as a conservative estimate of the magnitude of the pressure effects above the reference pressure.
16. This indicates that the effects should be understood in terms of density rather than pressure, because the strongest pressure dependence parallels the strongest density changes (and hence the strongest changes in molecular interactions). Because fluid pressure rather than density is the commonly used variable in geochemistry, the relation to pressure has been kept throughout the present communication.
17. L. Haar, J. S. Gallagher, G. S. Kell, NBS/NRC Steam Tables (1983).
18. R. N. Clayton et al., Geochim. Cosmochim. Acta 39, 1197 (1975).
19. C. M. Graham, S. M. F. Sheppard, T. H. Heaton, ibid. 44, 353 (1980).
20. T. W. Vennemann and J. R. O'Neil, ibid. 60, 2437 (1996).
21. H. E. Suess, Z. Naturforsch. 4a, 328 (1949); E. Cerrai et al., Chem. Eng. Prog. Symp. Ser. 50, 271 (1958).
22. H. E. Suess, Z. Naturforsch. 4a, 328 (1949); E. Cerrai et al., Chem. Eng. Prog. Symp. Ser. 50, 271 (1958).
23. P. Richet, Y. Bottinga, M. Javoy, Annu. Rev. Earth Planet Sci. 5, 65 (1977).
24. J. Horita and D. J. Wesolowski, Geochim. Cosmochim. Acta 58, 3425 (1994).
25. Evidence for such clusters comes from the lowpressure Raman spectra of Frantz et al. (5), as well as from molecular dynamics simulations [Y. Guissani and B. Guillot, J. Chem. Phys. 98, 8221 (1993)].
26. cluster-monomer was taken as the average cluster-monomer fractionation. Calculations at the MP2/6-31G** level gave essentially identical fractionation factors when the scaling factors given by Scott and Radom were used. The vapor-monomer fractionation is directly calculated from these results. Changing parameters like the geometric definition of clusters within reasonable limits indicate uncertainties in this approach of less than 5 per mil at 400°C and of about 1 per mil at 200°C.
27. cluster-monomer was taken as the average cluster-monomer fractionation. Calculations at the MP2/6-31G** level gave essentially identical fractionation factors when the scaling factors given by Scott and Radom were used. The vapor-monomer fractionation is directly calculated from these results. Changing parameters like the geometric definition of clusters within reasonable limits indicate uncertainties in this approach of less than 5 per mil at 400°C and of about 1 per mil at 200°C.
28. cluster-monomer was taken as the average cluster-monomer fractionation. Calculations at the MP2/6-31G** level gave essentially identical fractionation factors when the scaling factors given by Scott and Radom were used. The vapor-monomer fractionation is directly calculated from these results. Changing parameters like the geometric definition of clusters within reasonable limits indicate uncertainties in this approach of less than 5 per mil at 400°C and of about 1 per mil at 200°C.
29. cluster-monomer was taken as the average cluster-monomer fractionation. Calculations at the MP2/6-31G** level gave essentially identical fractionation factors when the scaling factors given by Scott and Radom were used. The vapor-monomer fractionation is directly calculated from these results. Changing parameters like the geometric definition of clusters within reasonable limits indicate uncertainties in this approach of less than 5 per mil at 400°C and of about 1 per mil at 200°C.
30. Furthermore, pressure effects explain many details in the data set of Graham et al. (75) that otherwise are not understandable. At 250°C their 400-WPa fractionation curve lies ∼4 to 5 per mil higher than the 200-MPa curve. A rough extrapolation of Fig. 1A to higher pressures predicts a similar, though slightly smaller, shift. At 350°C, the same equilibrium fractionation was measured for the two different pressures. Inspection of Fig. 1B reveals a straightforward explanation: At 200 MPa and 350°C, the contour lines of the pressure effect lie very close together, and a temperature variation of 5°C [the stated uncertainty of Graham et al. (15)] can cause a change in the fractionation by a few per mil.
31. T. Suzuoki and S. Epstein, Geochim. Cosmochim. Acta 40, 1229 (1976). These authors did not give information about the pressure in their experiments, but in the light of the present results, their 400° and 450°C data are likely to have been generated at about 250 to 400 bars.
32. C. M. Graham, R. S. Hamnon, S. M. F. Sheppard, Am. Mineral. 69, 128 (1984).
33. H. A. Gilg and S. M. F. Sheppard, Geochim. Cosmochim. Acta, 60, 3, 529 (1996).
34. R. E. Stoffregen, R. O. Rye, M. D. Wasserman, ibid. 58, 903 (1994).
35. T. Driesner, thesis, Eidgenössische Technische Hochschule-Zürich (1996); K. Shmulovich et al., Terra Nova 9, 540 (1997).
36. T. Driesner, thesis, Eidgenössische Technische Hochschule-Zürich (1996); K. Shmulovich et al., Terra Nova 9, 540 (1997).