Abstract
The new results of an experimental study of the majorite MgSiO3–magnesiochromite MgCr2O4 model section are discussed, and general topology of the SiO2–MgO–Cr2O3 system is analyzed. Despite the absence of some petrogenic components (CaO, FeO, Al2O3, Na2O, K2O, and others) in this system, our study, performed in wide pressure range (10–24 GPa), allows us to consider all of the most important phase transformations (in this case, magnesium silicates and oxides) in the upper mantle, transition zone, and uppermost lower mantle. Addition of Cr shows the influence of a minor element on the phase transition parameters. New data on the solubility of Cr in deep minerals (garnet, olivine, wadsleyite, ringwoodite, and bridgmanite) were obtained, which allowed us to determine the influence of Cr on the structural patterns of the major mantle phases. It is shown that addition of 1 wt % Cr2O3 shifts the boundaries of phase transformations by 50 km (olivine/wadsleyite) and 10 km (wadsleyite/ringwoodite) to a lower-pressure domain in comparison with Cr-free systems. In a first approximation, the results of experimental study of phase relations in pseudobinary sections of the SiO2–MgO–Cr2O3 system simulate the phase composition of the restitic part of the upper mantle, transition zone, and uppermost lower mantle under partial melting conditions. It is shown that the Cr concentration in mantle phases is significantly controlled by the Cr/Al ratio in the protolith.
Similar content being viewed by others
REFERENCES
Akaogi, M., Phase transitions of minerals in the transition zone and upper part of the lower mantle, Geol. Soc. Am., Sp. Pap., 2007, vol. 421, pp. 1–13.
Akaogi, M., Ito, E., and Navrotsky, A., The olivine-modified spinel–spinel transitions in the system Mg2SiO4–Fe2SiO4: calorimetric measurements, thermochemical calculation, and geophysical application, J. Geophys. Res., 1989, vol. 94, pp. 15671–15685.
Andrault, D., Properties of lower–mantle Al-(Mg,Fe)SiO3 perovskite, Geol. Soc. Am., Sp. Pap., 007, vol. 421, pp. 15–36.
Bindi, L., Sirotkina, E.A., Bobrov, A.V., and Irifune, T., Chromium solubility in MgSiO3 ilmenite at high pressure, Phys. Chemistry Miner., 2014, vol. 41, pp. 519–526.
Bulatov, V., Brey, G.P., and Foley, S.F., Origin of low-Ca, high-Cr garnets by recrystallization of low-pressure harzburgites, Extended Abstracts of 5th International Kimberlite Conference, Araxa, Brazil, 1991, CPRM Sp. Publ. 2/91, 29–31 (1999).
Dobrzhinetskaya, L., Green, H.W., and Wang, S., Alpe Arami: a peridotite massif from depths of more than 300 kilometers, Science, 1996, vol. 271, pp. 1841–1845.
Dobson, D.P. and Jacobsen, S.D., The flux growth of magnesium silicate perovskite single crystals, Am. Mineral., 2004, vol. 89, pp. 807–811.
Dymshits, A.M., Litasov, D., Sharygini, S., et al. Thermal equation of state of majoritic knorringite and its significance for continental upper mantle, J. Geophys. Res: Solid Earth, 2014, vol. 119, p. 1002. doi 10.1002/2014JB011194
Fei, Y., Van Orman, J., Li, J., et al., Experimentally determined post-spinel transformation boundary in Mg2SiO4 using MgO as an internal pressure standard and its geophysical implications, J. Geophys. Res., 2004, vol. 109, p. B02305.
Griffin, W.L., Afonso, J.C., Belousova, E.A., et al., Mantle recycling: transition zone metamorphism of Tibetan ophiolitic peridotites and its tectonic implications, J. Petrol., 2016, vol. 57, no. 4, pp. 655–684.
Harte, B., Harris, J.W., Hutchison, M.T., et al., Lower mantle mineral associations in diamonds from Sao Luiz, Brazil, Mantle Petrology: Field Observations and High Pressure Experimentation: A Tribute to Francis R. (Joe) Boyd, Houston: The Geochemical Society, 1999, no. 6, pp. 125–153.
Hirose, K., Phase transitions in pyrolitic mantle around 670-km depth: implications for upwelling of plumes from the lower mantle, J. Geophys. Res., 2002, vol. 107, p. 1029. doi 10.1002/2014JB011194
Irifune, T., Ohtani, E., and Kumazawa, M., Stability field of knorringite Mg3Cr2Si3O12 at high pressure and its implication to the occurrence of Cr-rich pyrope in the upper mantle, Phys. Earth Planet. Inter., 1982, vol. 27, pp. 263–272.
Irifune, T. and Ringwood, A.E., Phase transformations in a harzburgite composition to 26 GPa: implications for dynamical behaviour of the subducting slab, Earth Planet. Sci. Lett., 1987, vol. 86, pp. 365–376.
Irifune, T., Fujino, K., and Ohtani, E., A new high-pressure form of MgAl2O4, Nature, 1991, vol. 349, pp. 409–411.
Irifune, T., Koizumi, T., and Ando, J.I., An experimental study of the garnet–perovskite transformation in the system MgSiO3–Mg3Al2Si3O12, Phys. Earth Planet. Inter., 1996, vol. 96, pp. 147–157.
Irifune, T., Kurio, A., Sakamoto, S., et al., Formation of pure polycrystalline diamond by direct conversion of graphite at high pressure and high temperature, Phys. Earth Planet. Inter., 2004, vol. 143, pp. 593–600.
Ishii, T., Kojitani, H., Fujino, K., et al., High-pressure high-temperature transitions in MgCr2O4 and crystal structures of new Mg2Cr2O5 and post-spinel MgCr2O4 phases with implications for ultra-high pressure chromitites in ophiolites, Am. Mineral., 2015, vol. 100, pp. 59–65.
Ito, E. and Takahashi, E., Postspinel transformations in the system Mg2SiO4–Fe2SiO4 and some geophysical implications, J. Geophys. Res., 1989, vol. 94, no. B8, pp. 10637–10646.
Juhin, A., Morin, G., Elkaim, E., et al., Structure refinement of a synthetic knorringite, Mg3(Cr0.8Mg0.1Si0.1)2(SiO4)3, Am. Mineral., 2010, vol. 95, pp. 59–63.
Kaminsky, F.V., Zakharchenko, O.D., Davies, R., et al., Superdeep diamonds from the Juina area, Mato Grosso State, Brazil, Contrib. Mineral. Petrol., 2001, vol. 140, pp. 734–753.
Kaminsky, F.V., Mineralogy of the lower mantle: a review of super-deep mineral inclusions in diamond, Earth Sci. Rev., 2012, vol. 110, pp. 127–147.
Kojitani, H., Hisatomi, R., and Akaogi, M., High-pressure phase relations and crystal chemistry of calcium ferrite-type solid solutions in the system MgAl2O4–Mg2SiO4, Am. Mineral., 2007, vol. 92, pp. 1112–1118.
Liang, F., Yang, J., Xu, Z., and Zhao, J., Moissanite and chromium-rich olivine in the Luobusa mantle peridotite and chromitite, Tibet: deep mantle origin implication, J. Himal. Earth Sci., 2014, spec. vol., p. 103.
Malinovskii, I.Yu., Doroshev, A.M., Ran, and E.N., Stability of chromoium-bearing garnets of the pyrope–knorringite series, Eksperimental’nye issledovaniya po mineralogii (1974–1975) (Experimental Studies on Mineralogy (1974–1975)), Sobolev, V.S. and Godovikov, A.A., et al., Novosibirsk: In-t geologii i geofiziki SO AN SSSR, 1975, pp. 110–115.
Ottonello, G., Bokreta, M., and Sciuto, P.F., Parameterization of energy an interactions in garnets: end-member properties, Am. Mineral., 1996, vol. 81, pp. 429–447.
Panero, W.R., Akber-Knutson, S., and Stixrude, L., Al2O3 incorporation in MgSiO3 perovskite and ilmenite, Earth Planet. Sci. Lett., 2006, vol. 252, pp. 152–161.
Parise, J., Wang, Y., Dwanmesia, G.D., et al., The symmetry of garnets on the pyrope (Mg3Al2Si3O12)–majorite (MgSiO3) join, Geophys. Res. Lett., 1996, vol. 23, no. 25, pp. 3799–3802.
Ringwood, A.E. and Major, A., Some high-pressure transformations in olivines and pyroxenes, J. Geophys. Res., 1966, vol. 71, pp. 4448–4449.
Ringwood, A.E., The Chemical Composition and Origin of the Earth, Hurley, P.M., Ed., Advances in Earth Science, Cambridge: M.I.T. Press, 1966.
Ringwood, A.E. and Major, A., The system Mg2SiO4–Fe2SiO4 at high pressures and temperatures, Phys. Earth Planet. Inter., 1970, vol. 89, p. 3.
Ringwood, A.E. and Irifune, T., Nature of the 650-km seismic discontinuity: implications for mantle dynamics and differentiation, Nature, 1988, vol. 331, pp. 131–136.
Ryabchikov, I.D., Mechanisms and conditions of magma formation in mantle plumes, Petrology, 2003, vol. 11, no. 6, pp. 496–503.
Ryabchikov, I.D. and Kaminsky, F.V., The composition of the lower mantle: evidence from mineral inclusions in diamonds, Dokl. Earth Sci., 2013, vol. 453, pp. 1246–1249.
Ryabchikov, I.D., Brey, G.P., and Bulatov, V.K., Carbonate melts in equilibrium with mantle peridototes at 50 kbar, Petrologiya, 1993, vol. 1, no. 2, pp. 189–194.
Ryabchikov, I.D., Ionov, D.A., Kogarko, L.N., and Kovalenko, V.I., Chemical variations in mantle peridotites as result of different degree of partial melting of primitive mantle, Dokl. Akad. Nauk SSSR, 1987, vol. 295, no. 1, pp. 185–189.
Sirotkina, E.A., Bobrov, A.V., Bindi, L., and Irifune, T., Chromium-bearing phases in the Earth’s mantle: evidence from experiments in the Mg2SiO4–MgCr2O4 system at 10–24 GPa and 1600°C, Am. Mineral., 2018a, vol. 103, no. 1, pp. 151–160.
Sirotkina, E.A., Bobrov, A.V., Bindi, L., and Irifune, T., Phase relations and formation of chromium-rich phases in the system Mg4Si4O12–Mg3Cr2Si3O12 at 10–24 GPa and 1600oC, Contrib. Mineral. Petrol., 2015, vol. 169, p. 1007.
Sirotkina, E.A., Bindi, L., Bobrov, A.V., et al., Synthesis and crystal structure of chromium-bearing anhydrous wadsleyite, Phys. Chem. Mineral., 2018b, p. 1–6. doi 10.1007/s00269-017-0926-x
Sobolev, N.V., Diamond parageneses and the problem of deep-seated mineral formation, Zap. Vsesoyuz. Mineral. O-va, 1983, no. 4, pp. 389–397.
Stachel, T., Harris, J.W., and Brey, G.P., Rare and unusual mineral inclusions in diamonds from Mwadui, Tanzania, Contrib. Mineral. Petrol., 1998, vol. 132, pp. 34–47.
Stachel, T., Brey, G.P., and Harris, J.W., Kankan diamonds (Guinea) I: from the lithosphere down to the transition zone, Contrib. Mineral. Petrol., 2000a, vol. 140, pp. 1–15.
Stachel, T., Harris, J.W., Brey, G.P., and Joswig, W., Kankan diamonds (Guinea) II: Lower mantle inclusion parageneses, Contrib. Mineral. Petrol., 2000b, vol. 140, pp. 16–27.
Taylor, L.A. and Anand, M., Diamonds: time capsules from the Siberian mantle, Chem. Erde, 2004, vol. 64, pp. 1–74.
Turkin, A.I. and Sobolev, N.V., Pyrope–knorringite garnets: overview of experimental data and natural parageneses, Russ. Geol. Geophys., 2009, vol. 50, no. 12, pp. 1169–1182.
Yamamoto, S., Komiya, T., Hirose, K., and Maruyama, S., Coesite and clinopyroxene exsolution lamellae in chromites: in-situ ultrahigh-pressure evidence from podiform chromitites in the Luobusa Ophiolite, Southern Tibet, Lithos, 2009, vol. 109, pp. 314–322.
Zedgenizov, D.A., Shatskii, V.S., Panin, A.V., et al., Evidence for phase transitions in mineral inclusions in superdeep diamonds of the Sao Luiz deposit, Brazil, Russ. Geol. Geophys., 2015, vol. 56, nos. 1–2, pp. 296–305.
ACKNOWLEDGMENTS
The experimental and structural study was supported by the Russian Science Foundation, project no. 17-17-01169. In this study, we used the author’s database of high-pressure phase associations, created with the support of Program 8P no. 0137-2018-0043.
This study was supported by the Russian Science Foundation, project no. 17-17-01169.
Author information
Authors and Affiliations
Corresponding authors
Additional information
Translated by A. Bobrov
Rights and permissions
About this article
Cite this article
Matrosova, E.A., Bobrov, A.V., Bindi, L. et al. Phase Relations in the Model System SiO2–MgO–Cr2O3: Evidence from the Results of Experiments in Petrologically Significant Sections at 12–24 GPa and 1600°C. Petrology 26, 588–598 (2018). https://doi.org/10.1134/S0869591118060048
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1134/S0869591118060048