Contributions to Mineralogy and Petrology

, Volume 71, Issue 3, pp 219–235 | Cite as

Phase equilibria involving humite minerals in impure dolomitic limestones

Part I. Calculated stability of clinohumite
  • Jack M. Rice


The natural occurrence of critical assemblages among the phases clinohumite, calcite, dolomite, tremolite, forsterite, diopside, chlorite, and spinel in metamorphosed impure limestones, together with experimental and thermodynamic data, permits the calculation of phase equilibria governing the stability of clinohumite in terms of the variables P, T, and composition of a CO2-H2O-HF fluid. Equilibrium constant expressions are given for 23 equilibria that describe the stable phase relations between the above phases. Pure OH-clinohumite is considered to be metastable at relatively low pressures. The occurrence of clinohumite in natural marbles is the result of nonideal fluorine substitution which increases the stability of clinohumite. The stability field for clinohumite +calcite, governed primarily by the equilibrium 4forsterite+dolomite+H2O = clinohumite+calcite +CO2, expands to more CO2-rich fluid compositions with increasing fluorine contents and decreasing total pressure. The F/(F+OH) ratio of clinohumite coexisting with calcite, dolomite, and forsterite is a sensitive indicator of the composition of the mixedvolatile fluid phase. The thermodynamic model is in good agreement with observed phase relations and can be used to gain useful information concerning the P-T-Xfluid conditions responsible for the formation of clinohumite.


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. Aoki, A., Fujino, K., Akaogi, M.: Titanochondrodite and titanoclinohumite from the upper mantle in the Buell Park kimberlite, Arizona. Contrib. Mineral. Petrol. 56, 243–253 (1976)CrossRefGoogle Scholar
  2. Becker, P., Hoschek, G.: Experimentelle Bildung von Klinohumit. Neues Jahrb. Mineral. Monatsh. 6, 281–287 (1973)Google Scholar
  3. Bourne, J.H.: The petrogenesis of the humite group minerals in regionally metamorphosed marbles of the Grenville supergroup. Ph.D. Thesis, Queens's University (1974)Google Scholar
  4. Bowman, J.R., Essene, E.J.: Contact metamorphism of chloritebearing dolomites at Elkhorn, Montana. Geol. Soc. Am. Abstr. Progr. 9, 908 (1977)Google Scholar
  5. Bradshaw, R., Leake, B.E.: A chondrodite-humite-spinel marble from Sorfirnset near Glomfjord, northern Norway. Mineral. Mag. 33, 1066–1080 (1964)Google Scholar
  6. Burnham, C.W.: Cotact metamorphism of magnesian limestones at Crestmore, California. Geol. Soc. Am. Bull. 70, 879–920 (1959)Google Scholar
  7. Burnham, C.W., Holloway, J.R., Davis, N.E.: Thermodynamic properties of water to 1,000 ° C and 10,000 bars. Geol. Soc. Am. Spec. Pap. 132 (1969)Google Scholar
  8. Deer, W.A., Howie, R.A., Zussman, J.: Rock-Forming Minerals. Vol. 1, p. 333. London: Longmans 1967Google Scholar
  9. Dietrich, V.: Die Ophiolithe des Oberhalbsteins (Graubünden) und das Ophiolithmaterial der ostschweizerischen Molasseablagerungen, ein petrographischer Vergleich. Dissertation ETH Zürich. Bern: Verlag Herbert Lang & Cie. 1969Google Scholar
  10. Duffy, C.J.: Phase equilibria in the system MgO-MgF2-SiO2-H2O. In: Ph.D. Thesis, p. 70. Vancouver: University of British Columbia 1977Google Scholar
  11. Duffy, C.J., Greenwood, H.J.: Phase equilibria in the system MgO-MgF2-SiO2-H2O. Am. Mineral. (1979, in press)Google Scholar
  12. Evans, B.W., Trommsdorff, V.: Regional metamorphism of ultramafic rocks in the central Alps: Parageneses in the system CaO-MgO-SiO2-H2O. Schweiz. Mineral. Petrogr. Mitt. 50, 481–492 (1970)Google Scholar
  13. Fawcett, J.J., Yoder, H.S.: Phase relations of chlorites in the system MgO-Al2O3-SiO2-H2O. Am. Mineral. 51, 353–380 (1966)Google Scholar
  14. Fujii, T., Eitel, W.: Solid state reactions in the system MgO-MgF2-SiO2. Radex Rundsch. 445–469 (1957)Google Scholar
  15. Gasparrini, E.L., Gittins, J., Rucklidge, J.: Chemical variation among the noncarbonate minerals of the Cargill Lake carbonatite, Ontario. (Abs.) Can. Mineral. 10, 913 (1971)Google Scholar
  16. Heinrich, E.W.: Microscopic identification of minerals, p. 414. New York: McGraw-Hill Co. 1965Google Scholar
  17. Hinz, W., Kunth, P.O.: Phase equilibrium data for the system MgO-MgF2-SiO2. Am. Mineral. 45, 1198–1210 (1960)Google Scholar
  18. Holloway, J.R.: Fugacity and activity of molecular species in supercritical fluids. In: Thermodynamics in Geology (D.G. Fraser, ed.), Vol. 419, pp. 161–183. Boston: D. Reidel Co. 1976Google Scholar
  19. Jones, N.W., Ribbe, P.H., Gibbs, G.V.: Crystal chemistry of the humite minerals. Am. Mineral. 54, 391–411 (1969)Google Scholar
  20. Karyakin, L.I., Gul'ko, N.V.: Genesis of cuspidine and the minerals of the humite group. Dokl. Adak. Nauk. SSSR 96, 581 (1954)Google Scholar
  21. Kerrick, D.M., Crawford, K.E., Randazzo, A.F.: Metamorphism of calcareous rocks in three roof pendants in the Sierra Nevada, California. J. Petrol. 14, 303–325 (1973)Google Scholar
  22. McCormick, G.R.: Subsolidus compatibility relations in the system MgO-SiO2-MgF2. Radex Rundsch. 325–328 (1966)Google Scholar
  23. McGetchin, T.R., Silver, L.T., Chodos, A.A.: Titanoclinohumite: a possible mineralogical site for water in the upper mantle. J. Geophys. Res. 75, 255–259 (1970)Google Scholar
  24. Merrill, R.: Stability of titanoclinohumite and the role of water in the upper mantle. Geol. Soc. Am. Abstr. Progr. 2, 620–621 (1970)Google Scholar
  25. Misch, P.: Plagioclase compositions and the non-anatectic origin of migmatitic gneisses in northern Cascade mountains of Washington State. Contrib. Mineral. Petrol. 17, 1–70 (1968)CrossRefGoogle Scholar
  26. Moore, J.N., Kerrick, D.M.: Equilibria in siliceous dolomites of the Alta aureoli, Utah. Am. J. Sci. 276, 502–524 (1976)Google Scholar
  27. Munoz, J.L., Luddington, S.D.: Fluoride-hydroxyl exchange in biotite. Am. J. Sci. 274, 396–413 (1974)Google Scholar
  28. Rankama, K.: Synthesis of norbergite and chondrodite by direct dry fusion. Am. Mineral. 32, 146–157 (1947)Google Scholar
  29. Ribbe, P.H., Gibbs, G.V., Jones, N.W.: Cation and anion substitutions in the humite minerals. Mineral. Mag. 37, 966–975 (1968)Google Scholar
  30. Rice, J.M.: Phase equilibria and chemistry of metamorphosed impure dolomite, Ross Lake, Washington. Geol. Soc. Abstr. Progr. 5, 96 (1973)Google Scholar
  31. Rice, J.M.: Contact metamorphism of impure dolomitic limestone in the Boulder aureole, Montana. Contrib. Mineral. Petrol. 59, 237–259 (1977a)CrossRefGoogle Scholar
  32. Rice, J.M.: Progressive metamorphism of impure dolomitic limestone in the Marysville aureole, Montana. Am. J. Sci. 277, 1–24 (1977b)Google Scholar
  33. Rice, J.M.: Petrology of clintonite-bearing marbles in the Boulder aureole, Montana. Am. Mineral. 64, 519–527 (1979)Google Scholar
  34. Robie, R.A., Hemmingway, B.S., Fisher, J.R.: Thermodynamic properties of minerals and related substances at 298.15 ° K and 1 bar (105 pascals) pressure and at higher temperatures. U.S. Geol. Surv. Bull. 1452, 456 (1978)Google Scholar
  35. Sahama, Th.G.: Mineralogy of the humite group. Ann. Acad. Sci. Fenn. Ser. A3: 31, 1–50 (1953)Google Scholar
  36. Schmulovich, K.I., Shmomov, V.M.: Fugacity coefficients for CO2 from 1.0132 to 10,000 bars and 450–1,300 ° K. Geochem. Int. 12, 202–206 (1975)Google Scholar
  37. Skippen, G.B.: Experimental data for reactions in siliceous marbles. J. Geol. 79, 451–481 (1971)Google Scholar
  38. Skippen, G.B.: An experimental model for low pressure metamorphism of siliceous dolomitic marble. Am. J. Sci. 274, 487–509 (1974)Google Scholar
  39. Skippen, G.B., Yzerdraat, W.: XCDFOR, A FORTRAN IV Program for calculating equilibria on T-X CO 2 sections. Ottawa, Canada: Carleton Univ. Geol. Pap. 1970–1973 (1970)Google Scholar
  40. Skippen, G.B., Trommsdorff, V.: Invariant phase relations among minerals on T-Xfluid sections. Am. J. Sci. 275, 561–572 (1975)Google Scholar
  41. Slaughter, J., Kerrick, D.M., Wall, V.J.: Experimental and thermodynamic study of equilibria in the system CaO-MgO-SiO2-H2O-CO2. Am. J. Sci. 275, 143–162 (1975)Google Scholar
  42. Struwe, H.: Data on the mineralogy and petrology of the dolomitebearing northern contact zone of the Quérigut granite, French Pyrenees. Leidse. Geol. Meded. 22, 237–349 (1958)Google Scholar
  43. Tell, I.: Hydrothermal studies on fluorine metamorphic reactions in siliceous dolomite. Contrib. Mineral. Petrol. 43, 99–110 (1974)CrossRefGoogle Scholar
  44. Tilley, C.E.: The zoned contact skarns of the Broadford area, Skye: A study of boron-fluorine metasomatism. Mineral. Mag. 29, 621–660 (1951)Google Scholar
  45. Thompson, J.B. Jr.: Thermodynamic properties of simple solutions. In: Researches in Geochemistry II. (P.H. Abelson, ed.), pp. 340–361. New York: John Wiley and Sons 1967Google Scholar
  46. Thompson, J.B. Jr.: Biopyriboles and polysomatic series. Am. Mineral. 63, 239–250 (1978)Google Scholar
  47. Trommsdorff, V.: Beobachtungen zur Paragenese Forsterit (Klinohumit, Condrodit)-klinochlor in metamorphen Dolomitgesteinen des Lepontins. Schweiz. Mineral. Petrogr. Mitt. 46, 421–429 (1966)Google Scholar
  48. Trommsdorff, V., Evans, B.W.: Titanian hydroxyl-clinohumite: Formation and breakdown in antigorite rocks. Contrib. Mineral. Petrol. (1980, in press)Google Scholar
  49. Valkenburg, A. van: Synthesis of the humites. Am. Mineral. 40, 339 (1955)Google Scholar
  50. Valkenburg, A. van: Synthesis of the humites nMg2SiO4Mg(OH,F)2. J. Res. Nat. Bur. Stand. Sect. A: 65, 415–428 (1961)Google Scholar
  51. Watanabe, T.: Geology and mineralization of the Suian District, Tyosen (Korea). J. Fac. Sci. Hokkaido Univ. Ser. 4+6: 3–4 (1943)Google Scholar
  52. Wenk, E.: Klinohumit und Chondrodit in Marmoren der Tessiner Alpen und der Disgrazia Gruppe. Schweiz. Mineral. Petrogr. Mitt. 43, 287–293 (1963)Google Scholar

Copyright information

© Springer-Verlag 1980

Authors and Affiliations

  • Jack M. Rice
    • 1
  1. 1.Department of GeologyUniversity of OregonEugeneUSA

Personalised recommendations