Abstract
New heat capacity measurements and cell volume data are presented for a very magnesian glaucophane from a Tauern Window eclogite. These data are combined with estimated entropy, thermal expansion, and compressibility data to generate an enthalpy of formation for glaucophane from experimentally determined phase equilibria. The data are supported by preliminary experiments of the author and provide consistent calculations on the pressure of formation of the Tauern eclogites and on the position of the blueschist-greenschist transformation reaction as studied experimentally by Maruyama et al. (1986). The resulting thermodynamic data for glaucophane may be combined with the dataset of Holland and Powell (1985) to calculate phase relations for blueschists and eclogites. The stability of magnesian glaucophane lies in the pressure range between 8 and 32 kbars at 400° C and between 13 and 33 kbars at 600° C, and the unusual eclogite assemblage of glaucophane+kyanite from the Tauern Window is restricted to pressures above 20 kbars at high water activity.
Similar content being viewed by others
References
Berman RG, Brown TH (1985) Heat capacity of minerals in the system Na2O-K2O-CaO-MgO-FeO-Al2O3-SiO2-TiO2-H2O-CO2: representation, estimation, and high temperature extrapolation. Contrib Mineral Petrol 89:168–183
Borg IY (1967) Optical and cell parameters in the glaucophaneriebeckite series. Contrib Mineral Petrol 15:67–92
Carman JH, Gilbert MC (1983) Experimental studies on glaucophane stability. Am J Sci 283A:414–437
Chen CH (1975) A method of estimation of standard free energies of formation of silicate minerals at 298.15 K. Am J Sci 275:801–817
Chopin C, Schreyer W (1983) Magnesiocarpholite and magnesiochloritoid: two index minerals of pelitic blueschists and their preliminary phase relations in the model system MgO-Al2O3- SiO2-H2O. Am J Sci 283A:72–96
Coleman RG, Papike JJ (1968) Alkali amphiboles from the blueschists of Cazadero, California. J Petrol 9:105–122
Colville P, Ernst WG, Gilbert MC (1966) Relationships between cell parameters and chemical composition of monoclinic amphiboles. Am Mineral 51:1727–1754
Ditmars DA, Douglas TB (1971) Measurement of the relative enthalpy of pure Al2O3 (NBS heat capacity and enthalpy standard reference material no. 720) from 273 to 1173 K. J Res Nat Bur Stds 75A:401–420
Ernst WG (1963) Polymorphism in alkali amphiboles. Am Mineral 48:241–260
Ernst WG (1964) Petrochemical study of coexisting minerals from low grade schists, Eastern Shikoku, Japan. Geochim Cosmochim Acta 28:1631–1668
Helgeson HC, Delaney JR, Nesbitt HW, Bird DK (1978) Summary and critique of the thermodynamic properties of rock-forming minerals. Am J Sci 278A:1–229
Hoffman C (1972) Natural and synthetic ferroglaucophane. Contrib Mineral Petrol 34:135–149
Holland TJB (1979) High water activities in the generation of high pressure kyanite eclogites of the Tauern window, Austria. J Geol 87:1–27
Holland TJB (1980) The reaction albite=Jadeite+quartz determined experimentally in the range 600–1200° C. Am Mineral 65:129–134
Holland TJB (1981) Thermodynamics of simple mineral systems. In: Newton RC, Navrotsky A, Wood BJ (eds). Thermodynamics of minerals and melts. Springer, Berlin Heidelberg New York
Holland TJB, Powell R (1985) An internally consistent thermodynamic dataset with uncertainties and correlations. 2. Data and results. J Metam Geol 3:343–370
Holland TJB, Richardson SW (1979) Amphibole zonation in metabasites as a guide to the evolution of metamorphic conditions. Contrib Mineral Petrol 70:143–148
Koons PO (1982) An experimental investigation of the behaviour of amphibole in the system Na2O-MgO-Al2O3-SiO2-H2O at high pressures. Contrib Mineral Petrol 79:258–267
Likhoydov GG, Sidorov Yu I, Gurevich VM, Gorbunov V Ye, Lennykh VI, Velizer PN, Khodakovskiy IL (1982) The thermodynamic parameters of glaucophane Na2Mg3Al2Si8O22(OH)2 and some petrological consequences. Geochem Internat 19:66–77
Maresch WV (1977) Experimental studies on glaucophane: an analysis of present konwledge. Tectonophys 43:109–125
Maruyama S, Moonsup Cho, Liou JG (1986) Experimental investigations of blueschist-greenschist transition equilibria: pressure dependence of Al2O3 contents in sodic amphiboles — a new geobarometer. Geol Soc Am Mem 164:1–16
Papike JJ, Clarke JR (1968) The crystal structure and cation distribution of glaucophane. Am Mineral 53:1156–1173
Powell R (1985) Geothermometry and geobarometry: a discussion. J Geol Soc Lond 142:29–38
Powell R, Holland TJB (1985) An internally consistent thermodynamic dataset with uncertainties and correlations. 1 Methods and a worked example. J Metam Geol 3:327–342
Powell R, Holland TJB (1988) An internally consistent dataset with uncertainties and correlations: 3. applications to geobarometry, worked examples and a computer program. J Metam Geol (in press)
Robinson GR, Haas JL (1983) Heat capacity, relative enthalpy, and calorimetric entropy of silicate minerals: an empirical method of prediction. Am Mineral 68:541–553
Schliestedt M, Matthews A (1987) Transformation of blueschist to greenschist facies rocks as a consequence of fluid infiltration, Sifnos (Cyclades), Greece. Contrib Mineral Petrol 97:237–250
Tardy Y, Garrels RH (1974) A method of estimating the Gibbs energies of formation of layer silicates. Geochim Cosmochim Acta 48:1101–1116
Thompson JB Jr (1978) Biopyriboles and polysomatic series. Am Mineral 63:239–249
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Holland, T.J.B. Preliminary phase relations involving glaucophane and applications to high pressure petrology: new heat capacity and thermodynamic data. Contr. Mineral. and Petrol. 99, 134–142 (1988). https://doi.org/10.1007/BF00399373
Received:
Accepted:
Issue Date:
DOI: https://doi.org/10.1007/BF00399373