Abstract
Electrical conductivities of Ni2SiO4, Fe2SiO4, and MgSiO3 were measured on synthetic powders in the temperature range 340° to 1,100° C and at pressures up to 20 kbars. For ternary compounds such as olivines and pyroxenes the control of two further variables, like the chemical activities of two components are needed, besides temperature and pressure. The activities of the corresponding binary oxides were controlled by equilibrating the samples with their neighbour-phases. Control of the oxygen partial pressure was achieved by buffer techniques.
From the slopes of the lg σ vs. 1/T lines the activation energies were calculated for 10 kbar: 0.56 eV and 2.7 eV for Ni2SiO4 in equilibrium with SiO2 and Ni/NiO-buffer for the temperature range 500°–800°C and 800°–1,000°C resp. 0.52 eV for Fe2SiO4 in equilibrium with SiO2 and metallic iron, and 0.38 eV in equilibrium with SiO2 and magnetite; 1.11 eV for MgSiO3 in equilibrium with SiO2, and 1.25 eV in equilibrium with Mg2SiO4.
Similar content being viewed by others
References
Akimoto, S.I., Fujisawa, H.: Demonstration of the electrical conductivity jump produced by the olivine-spinel transition. J. Geophys. Res. 70, 443–449 (1965)
Bradley, R.S., Jamil, A.K., Munro, D.C.: The electrical conductivity of olivine at high temperatures and pressures. Geochim. Cosmochim. Acta 28, 1669–1678 (1964)
Bradley, R.S., Milnes, G.J., Munro, D.C.: The electrical conductivities at elevated temperatures and pressures of polycrystalline manganese, cobalt and nickel orthosilicate. Geochim. Cosmochim. Acta 37, 2379–2394 (1973)
Cemič, L., Hinze, E., Will, G.: Messungen der elektrischen Leitfähigkeit bei kontrollierten Sauerstoffaktivitäten in Druckapparaturen mit festen Druckübertragungsmedien. High Temp.-High Pressures 10, 469–472 (1978)
Cemič, L., Jansen, E.: Measurement of electrical conductivity in a solid medium high-pressure cell by means of an AC-bridge. High Temp.-High Pressures 7, 295–298 (1975)
Duba, A.: Electrical conductivity of olivine. J. Geophys. Res. 77, 2483–2495 (1972)
Duba, A.: Are laboratory electrical conductivity data relevant to the earth? Acta Geodaet. Geophys. et Montanist. Acad. Sci. Hung. 11 (3–4), 485–495 (1976)
Duba, A., Boland, J.N., Ringwood, A.E.: Electrical conductivity of pyroxene. J. Geol. 81, 727–735 (1973)
Duba, A., Heard, H.C., Schock, R.N.: Electrical conductivity of olivine at high pressure and under controlled oxygen fugacity. J. Geophys. Res. 79, 1667–1673 (1974)
Duba, A., Nicholls, A.: The influence of oxidation state on the electrical conductivity of olivine. Earth Planet. Sci. Lett. 18, 59–64 (1973)
Duba, A., Ringwood, A.E.: Temperatures in the lunar interior and some implications. Earth Planet. Sci. Lett. 18, 158–162 (1973)
Dvořák, Z., Schloessin, H.H.: On the anisotropic electrical conductivity of enstatite as a function of pressure and temperature. Geophysics 38, 25–36 (1973)
Greskovich, C., Schmalzried, H.: Nonstoichiometry and electronic defects in Co2SiO4 and in Co-Al2O4-MgAl2O4 crystalline solutions. J. Phys. Chem. Solids 31, 639–646 (1970)
Hamilton, R.M.: Temperature variation at constant pressures of the electrical conductivity of periclase and olivine. J. Geophys. Res. 70, 5679–5692 (1965)
Huebner, J.S., Sato, M.: The oxygen fugacity-temperature relationship of manganese oxide and nickel oxide buffers. Am. Mineral. 55, 934–952 (1970)
Kirfel, A., Neuhaus, A.: Messung hoher elektrischer Widerstände in geschlossenen Druckapparaturen. High Temp.-High Pressures 3, 81–87 (1971)
Kobayashi, Y., Maruyama, H.: Electrical conductivity of olivine single crystals at high temperature. Earth Planet. Sci. Lett. 11, 415–419 (1971)
Mao, H.K., Bell, P.M.: Electrical conductivity and the red shift of absorption in olivine and spinel at high pressure. Science 176, 403–406 (1972)
Mizutani, H., Kanamori, H.: Electrical conductivities of rock-forming minerals at high temperatures. J. Phys. Earth 15, 25–31 (1967)
Pluschkell, W., Engell, H.J.: Ionen- und Elektronenleitung im Magnesiumorthosilikat. Ber. Dtsch. Keram. Ges. 45, 388–394 (1968)
Schmalzried, H.: Point defects in ternary ionic crystals. In: Progress in solid state chemistry, Vol. 2, Reiss, H. (ed.). Oxford: Pergamon Press 1965, pp. 265–303
Schmalzried, H., Navrotsky, A.: Festkörperthermodynamik, Chemie des festen Zustandes. Weinheim: Verlag Chemie 1975
Shock, R.N., Duba, A.G., Heard, H.C., Stromberg, H.D.: The electrical conductivity of polycrystalline olivine and pyroxene under pressure. In: High pressure research, applications in geophysics, Manghani, M.H., Akimoto, S.I. (eds.). New York: Academic Press 1977, pp. 39–51
Shankland, T.J.: Electrical conduction in rocks and minerals: parameters for interpretation. Phys. Earth Planet. Inter. 10, 209–219 (1975)
Sockel, H.G.: Defect structure and electrical conductivity of crystalline ferrous silicate. In: Defects and transport in oxides, Schmelzer, N.S., Jaffe, R.J. (eds.). New York: Plenum Press 1974, pp. 341–355
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Will, G., Cemič, L., Hinze, E. et al. Electrical conductivity measurements on olivines and pyroxenes under defined thermodynamic activities as a function of temperature and pressure. Phys Chem Minerals 4, 189–197 (1979). https://doi.org/10.1007/BF00307562
Received:
Issue Date:
DOI: https://doi.org/10.1007/BF00307562