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Petrology

, Volume 27, Issue 4, pp 395–406 | Cite as

Equation of State of the H2O–CO2–CaCl2 Fluid System and Properties of Fluid Phases at Р-Т Parameters of the Middle and Lower Crust

  • M. V. IvanovEmail author
  • S. A. Bushmin
Article
  • 2 Downloads

Abstract

A numerical thermodynamic model is proposed for one of the most important geological fluid system, ternary H2O–CO2–CaCl2 system, at P-T conditions of the middle and lower crust and crust–mantle boundary. The model is based on the previously proposed equation for concentration dependence of the excess Gibbs free energy and on the first obtained P-T dependencies of the coefficients of the equation of state (EOS) expressed via molar volumes of the components. The EOS allows to predict the properties of the fluid participating in the majority of deep petrogenetic processes: its phase state (homogeneous or multi-phase), densities of fluid phases, concentrations of components in the co-existing phases, and the chemical activities of the components. The model precisely reproduces all available experimental data on the phase state of the ternary H2O–CO2–CaCl2 fluid system in the ranges of temperatures 773.15–1073.15 K and pressures 0.1–0.9 GPa and also allows the correct application of the EOS beyond the experimentally studied range of temperatures and pressures up to P = 2 GPa and T = 1673.15 K. The possibility of the correct extrapolation of our EOS is ensured by using the parametrization of P-T dependencies via the molar volume of water. The latter remains in the experimental domain of values or falls slightly beyond its boundaries, when increasing temperatures and pressures.

Keywords:

fluid equation of state H2O–CO2–CaCl2 phase splitting high temperature high pressure lower crust mantle 

Notes

ACKNOWLEDGMENTS

We are grateful to L. Ya. Aranovich (IGEM RAS) for useful and productive comments.

FUNDING

This work was supported by the State Task of the Institute of Precambrian Geology and Geochronology of the Russian Academy of Sciences (project no. 0153-2019-0004).

CONFLICT OF INTEREST

The authors declare that they have no conflict of interest.

REFERENCES

  1. 1.
    Aranovich, L.Ya., Fluid–mineral equilibria and thermodynamic mixing properties of fluid systems, Petrology, 2013, vol. 21, no. 6, pp. 527–538.CrossRefGoogle Scholar
  2. 2.
    Aranovich, L.Ya., The role of brines in high-temperature metamorphism and granitization, Petrology, 2017, vol. 25, no. 5, pp. 486–497.CrossRefGoogle Scholar
  3. 3.
    Aranovich, L.Ya., Zakirov, I.V., Sretenskaya, N.G., and Gerya, E.V., Ternary system H2O–CO2–NaCl at high TP parameters: an empirical mixing model, Geochem. Int., 2010, vol. 48, no. 5, pp. 446–455.CrossRefGoogle Scholar
  4. 4.
    Aranovich, L.Y. and Newton, R.C., H2O activity in concentrated NaCl solutions at high pressures and temperatures measured by the brucite–periclase equilibrium, Contrib. Mineral. Petrol., 1996, vol. 125, pp. 200–212.CrossRefGoogle Scholar
  5. 5.
    Aranovich, L.Y. and Newton, R.C., H2O activity in concentrated KCl and KCl–NaCl solutions at high temperatures and pressures measured by the brucite–periclase equilibrium, Contrib. Mineral. Petrol., 1997, vol. 127, pp. 261–271.CrossRefGoogle Scholar
  6. 6.
    Bischoff, J.L., Rosenbauer, R.J., and Fournier, R.O., The generation of HCl in the system CaCl2–H2O: vapor–liquid relations from 380–500°C, Geochim. Cosmochim. Acta, 1996, vol. 60, pp. 7–16.CrossRefGoogle Scholar
  7. 7.
    Bockris, J.O’M. and Richards, N.E., The compressibilities, free volumes and equation of state for molten electrolytes: some alkali halides and nitrates, Proc. R. Soc. London, Ser. A, 1957, vol. 241, pp. 44–66.CrossRefGoogle Scholar
  8. 8.
    Bockris, J.O’M., Pilla, A., and Barton, J.L., The compressibilities of certain molten alkaline earth halides and the volume change upon fusion of the corresponding solids, Rev. Chim. Acad. Rep. Popul. Roum., 1962, vol. 7, no. 1, pp. 59–77.Google Scholar
  9. 9.
    Bushmin, S.A., Ivanov, M.V., and Vapnik, E.A., Fluids of HP-granulites: phase state and geochemical implications, Sovremennye problemy magmatizma, metamorfizma i geodinamiki (Konferentsiya, posvyashchennaya 85-letiyu so dnya rozhdeniya L.L. Perchuka 23-24 noyabrya 2018 g.) (Modern Problems of Magmatism. Metamorphism, and Geodynamics. Conference in Honor of 85th Anniversary of L.L. Perchuk), Moscow: IEM RAN, 2018, pp. 24–25.Google Scholar
  10. 10.
    Bushmin, S.A., Vapnik, E.A., Ivanov, M.V., et al., Fluids of high-pressure granulites, Petrology, 2019 (in press).Google Scholar
  11. 11.
    Bushmin, S.A., Vapnik, E.A., Ivanov, M.V., et al., Fluids of high-pressure granulites: Lapland granulite belt (Fennoscandian Shield), Geodinamicheskie obstanovki i termodinamicheskie usloviya regional’nogo metamorfizma v dokembrii i fanerozoe (Geodynamic Settings and Thermodynamic Conditions of Regional Metamorphism in the Precambrian and Phanerozoic), St. Petersburg: IGGD RAN, 2017, pp. 40–43.Google Scholar
  12. 12.
    Chase, M.W., Jr., NIST-JANAF thermochemical tables, J. Phys. Chem. Ref. Data. Monogr., 1988, no. 9, pp. 1–1951.Google Scholar
  13. 13.
    Chou I-Ming, Phase relations in the system NaCl–KCl–H2O: III. Solubilities of halite in vapor-saturated liquids above 445°C and redetermination of phase equilibrium properties in the system NaCl–H2O to 1000°C and 1500 bars, Geochim. Cosmochim. Acta, 1987, vol. 51, pp. 1965–1975.Google Scholar
  14. 14.
    Diamond, L.W., Introduction to gas-bearing, aqueous fluid inclusions, Fluid Inclusions: Analysis and Interpretation, Samson, I., Anderson, A., Marshall, D., Eds., Mineral. Ass. Canad. Short Course Ser., 2003, vol. 32, pp. 101–158.Google Scholar
  15. 15.
    Driesner, T., The system H2O–NaCl. Part II: Correlations for molar volume, enthalpy, and isobaric heat capacity from 0 to 1000°C, 1 to 5000 bar, and 0 to 1 x NaCl, Geochim. Cosmochim. Acta, 2007, vol. 71, pp. 4902–4919.CrossRefGoogle Scholar
  16. 16.
    Duan, Z., Møller, N., and Weare, J.H., Equation of state for the NaCl–H2O–CO2 system: prediction of phase equilibria and volumetric properties, Geochim. Cosmochim. Acta, 1995, vol. 59, pp. 2869–2882.CrossRefGoogle Scholar
  17. 17.
    Dubacq, B., Bickle, M.J., and Evans, K.A., An activity model for phase equilibria in the H2O–CO2–NaCl system, Geochim. Cosmochim. Acta, 2013, vol. 110, pp. 229–252.CrossRefGoogle Scholar
  18. 18.
    Heinrich, W., Churakov, S.S., and Gottschalk, M., Mineral-fluid equilibria in the system CaO–MgO–SiO2–H2O–CO2–NaCl and the record of reactive fluid flow in contact metamorphic aureoles, Contrib. Mineral. Petrol., 2004, vol. 148, pp. 131–149.CrossRefGoogle Scholar
  19. 19.
    Heinrich, W., Fluid immiscibility in metamorphic rocks, Rev. Mineral. Geochem., 2007, vol. 65, pp. 389–430.CrossRefGoogle Scholar
  20. 20.
    Ivanov, M.V., Bushmin, S.A., and Aranovich, L.Ya., An empirical model of the Gibbs free energy for solutions of NaCl and CaCl2 of arbitrary concentration at temperatures from 423.15 K to 623.15 K under vapor saturation pressure, Dokl. Earth Sci., 2018a, vol. 479, no. 2, pp. 491–494.CrossRefGoogle Scholar
  21. 21.
    Ivanov, M.V., Bushmin, S.A., and Aranovich, L.Ya., Equations of state for NaCl and CaCl2 solutions of arbitrary concentration at temperatures 423.15–623.15 K and pressures up to 5 kbar, Dokl. Earth Sci., 2018b, vol. 481, no. 2, pp. 1086–1090.CrossRefGoogle Scholar
  22. 22.
    Ivanov, M.V., Complex rotation in two-dimensional mesh calculations for quantum systems in uniform electric fields, J. Phys. B, 2001, vol. 34, pp. 2447–2473.CrossRefGoogle Scholar
  23. 23.
    Janz, G.J., Thermodynamic and transport properties for molten salts: correlation equations for critically evaluated density, surface tension, electrical conductance, and viscosity data, J. Phys. Chem. Ref. Data, 1988, vol. 17, no. Suppl. 2, pp. 1–309.Google Scholar
  24. 24.
    Manning, C.E. and Aranovich, L.Y., Brines at high pressure and temperature: thermodynamic, petrologic and geochemical effects, Precambrian Res., 2014, vol. 253, pp. 6–16.CrossRefGoogle Scholar
  25. 25.
    Manning, C.E., Fluids of the lower crust: deep is different, Annu. Rev. Earth Planet. Sci., 2018, vol. 46, pp. 67–97.CrossRefGoogle Scholar
  26. 26.
    Mao, S., Hu, J., Zhang, Y., and Lu, M., A predictive model for the PVTx properties of CO2–H2O–NaCl fluid mixture up to high temperature and high pressure, Appl. Geochem., 2015, vol. 54, pp. 54–64.CrossRefGoogle Scholar
  27. 27.
    Markl, G. and Bucher, K., Composition of fluids in the lower crust inferred from metamorphic salt in lower crustal rocks, Nature, 1998, vol. 391, pp. 781–783.CrossRefGoogle Scholar
  28. 28.
    Newton, R.C. and Manning, C.E., Role of saline fluids in deep-crustal and upper-mantle metasomatism: insights from experimental studies, Geofluids, 2010, vol. 10, pp. 58–72.Google Scholar
  29. 29.
    Pistorius, C.W.F.T., Effect of pressure on the melting points of the sodium halides, J. Chem. Phys., 1966, vol. 45, pp. 3513–3519.CrossRefGoogle Scholar
  30. 30.
    Schinke, H. and Sauerwald, F., Über die Volumenänderung beim schmelzen und den Schmelzprozeß bei Salzen, Z. Anorg. Allg. Chem., 1952, vol. 287, pp. 313–324.CrossRefGoogle Scholar
  31. 31.
    Shmulovich, K.I. and Plyasunova, N.V., Phase equilibria in triple systems H2O–CO2–salt (CaCl2, NaCl) at high temperatures and pressures, Geokhimiya, 1993, no. 5, pp. 666–684.Google Scholar
  32. 32.
    Shmulovich, K.I. and Graham, C.M., An experimental study of phase equilibria in the systems H2O–CO2–CaCl2 and H2O–O2–NaCl at high pressures and temperatures (500–800°C, 0.5–0.9 GPa): geological and geophysical applications, Contrib. Mineral Petrol, 2004, vol. 146, pp. 450–462.CrossRefGoogle Scholar
  33. 33.
    Simon, F.E. and Glatzel, G., Bemerkungen zur schmelzdruckkurve, Z. Anorg. Allg. Chem., 1929, vol. 178, pp. 309–316.CrossRefGoogle Scholar
  34. 34.
    Span, R. and Wagner, W., A new equation of state for carbon dioxide covering the fluid region from the triple-point temperature to 1100 K at pressures up to 800 MPa, J. Phys. Chem. Ref. Data, 1996, vol. 25, pp. 1509–1596.CrossRefGoogle Scholar
  35. 35.
    Sterner, S.M., Chou I-Ming, Downs, R.T., and Pitzer, K.S., Phase relations in the system NaCl-KCl-H2O: V. Thermodynamic-PTX analysis of solid-liquid equilibria at high temperatures and pressures, Geochim. Cosmochim. Acta, 1992, vol. 56, pp. 2295–2309.CrossRefGoogle Scholar
  36. 36.
    Sun, R. and Dubessy, J., Prediction of vapor-liquid equilibrium and PVTx properties of geological fluid system with SAFT-LJ EOS including multi-polar contribution. Part II: application to H2O–NaCl and CO2–H2O–NaCl system, Geochim. Cosmochim. Acta, 2012, vol. 88, pp. 130–145.CrossRefGoogle Scholar
  37. 37.
    Trommsdorff, V., Skippen, G., and Ulmer, P., Halite and sylvite as solid inclusions in high-grade metamorphic rocks, Contrib. Mineral. Petrol., 1985, vol. 89, pp. 24–29.CrossRefGoogle Scholar
  38. 38.
    Wagner, W. and Pruß, A., The IAPWS formulation 1995 for the thermodynamic properties of ordinary water substance for general and scientific use, J. Phys. Chem. Ref. Data, 2002, vol. 31, pp. 387–535.CrossRefGoogle Scholar
  39. 39.
    Zhang, Y.-G. and Frantz, J.D., Experimental determination of the compositional limits of immiscibility in the system CaCl2–H2O–CO2 at high temperatures and pressures using synthetic fluid inclusions, Chem. Geol., 1989, vol. 74, pp. 289–308.CrossRefGoogle Scholar
  40. 40.
    Zhang, C. and Duan, Z.H., A model for C–O–H fluid in the Earth’s mantle, Geochim. Cosmochim. Acta, 2009, vol. 73, pp. 2089–2102.CrossRefGoogle Scholar

Copyright information

© Pleiades Publishing, Ltd. 2019

Authors and Affiliations

  1. 1.Institute of Precambrian Geology and Geochronology, Russian Academy of SciencesSt. PetersburgRussia

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