American Journal of Physical Chemistry

| Peer-Reviewed |

Genetic Role of Calcium Content in Olivine Crystals of Ultramafic and Mafic Rocks

Received: Apr. 14, 2020    Accepted: May 15, 2020    Published: May 29, 2020
Views:       Downloads:

Share This Article

Abstract

The results of genetic systematization of olivine compositions formed both under experimental conditions and its natural differences from rocks of basic and ultramafic compositions of various depth facies and formed in various geodynamic settings are presented. Similar work [53], performed in the 70s of the last century and has been actively cited to this day. Generalization of the subsequent accumulated data showed the error of one of the main conclusions in this work – the dependence of the Cao content in olivine on the hydrostatic pressure during its formation from the melt. According to experimental studies conducted in recent years, up to a pressure of 29 GPA, the content of calcium in olivine, which has grown from the main-ultrabasic melts, does not depend on the pressure and is not lower than 0.1 wt.% CaO. Experiments in solidus conditions involving fluid and natural data have demonstrated that one of the leading factors affecting the calcium content in olivine are metasomatic processes that lead to the removal of calcium from olivine crystals. The role of metasomatic transformations of olivine in terms of calcium content, despite the apparent insignificance of secondary changes in it, is clearly visible in the examples of basalts and gabbro of the modern oceanic crust and the same facies differences in ophiolite complexes. The wide development of metasomatic transformations of igneous rocks of various facies and ages indicates the need to take into account the calcium content in olivine as an equilibrium criterion when calculating temperatures and pressures for paragenesis involving olivine. Olivines, which are part of ultrabasic xenoliths carried out by sub-alkaline magmas, including those carried out by kimberlites, are overwhelmingly represented by low-calcium differences. Low levels of calcium in olivines from these mantle fragments suggest that magmatic melts of the main-ultramafic compositions are not in equilibrium with the mantle substance to depths of about ~ 200 km, and possibly more. Among the compositions of olivines from fresh effusive rocks, its inclusions and microlites are mostly represented by calcium-containing differences. Only in kimberlites, almost all the differences in its crystals (inclusions, microlites) in the rock are represented by low-calcium differences. Olivines included in diamonds are also overwhelmingly represented by low calcium differences. This suggests that the composition of kimberlite olivine is associated with metasomatic transformations, and the growth of diamonds from kimberlites is due to the fluid. Inside the natural single crystals of diamond, there are polymetallic films buried in the body of crystals. Similar films were formed on the faces of diamond crystals formed in the Lav pores (that is, almost on the surface of the day) in 2012-13 of the Tolbachinsky Fissure eruption. These data allow us to create artificial "soft" conditions (CVD, solution, etc.) for the growth of single-crystal diamond films on similar polymetallic or single-element films. For these purposes, elements such as zirconium, dysprosium, erbium, and others can be used.

DOI 10.11648/j.ajpc.20200902.11
Published in American Journal of Physical Chemistry ( Volume 9, Issue 2, June 2020 )
Page(s) 16-26
Creative Commons

This is an Open Access article, distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution and reproduction in any medium or format, provided the original work is properly cited.

Copyright

Copyright © The Author(s), 2024. Published by Science Publishing Group

Keywords

Calcium, Olivine, Equilibrium

References
[1] Aleksandrov, S. M. (2011). Metasomatic transformations of carbonate rocks observable in quarries of Riverside, California, United States. Geochemistry, 7, 751–766.
[2] Ariskin, A. A., Barmina, G. S. (2000). Computer simulation of phase equilibria during crystallization of basalt magma, Moscow: Science.
[3] Bobrov, A. V., Litvin, Yu. A. (2009). Peridotite-eclogite-carbonatite systems at 7.0–8.5 GPa: concentration barrier for diamond nucleation and syngenesis of its silicate and carbonatite inclusions. Geology and Geophysics, 50 (12), 1571–1587.
[4] Bureau, H., Frost, D. J., Bolfan-Casanova, N., Leroy, C., Esteve, I., Cordier, P. (2016). Diamond growth in mantle fluids. Lithos, 265, 4–15.
[5] Bussweiler, Y., Stone, R. S. Pearson, D. G., Luth, R. W., Stachel, T., Kjarsgaard, B. A., Menzies, A. (2016). The evolution of calcite-bearing kimberlites by melt-rock reaction: evidence from polymineralic inclusions within garnet and clinopyroxene megacrysts from Lac de Gras kimberlites, Canada. Contributions to Mineralogy and Petrology, 171: 65.
[6] Celik, O. F., Marsoli, A. Marschik, R., Chiaradia, M., Mathur, R. (2018). Geochemical, mineralogical and Re-Os isotopic constraints on the origin of Tethyan oceanic mantle and crustal rocks from the central Pontides, northern Turkey. Mineralogy and Petrology, 49 (112), 25–44.
[7] Chaschin, V. V. (2007). Mineral paragenesis and genesis conditions of hornstones in exocontact zone of the Khibiny alkaline pluton (Kola peninsula, Russia). Geochemistry, 1, 19–37.
[8] Chepurnov, A. I., Sonin, V. M., Tychkov, N. S., Kulakov, I. Yu. (2015) Experimental estimate of the actual infiltration (migration) of volatilities (H2O + CO2) in rocks of the mantle wedge. Doklady Akademii Nauk, 464 (1), 100–104.
[9] Chertkova, N., Yamachita, S., Ito, E., Shimojuku, A. (2014). High-pressure synthesis and application of a 13C diamond pressure sensor for experiments in a hydrothermal diamond anvil cell. Mineralogical Magazine, 78 (7), 1677–1685.
[10] Condamine, P., Medard, E. (2014). Experimental melting of phlogopite-bearing mantle at 1 GPa: implication for potassic magmatism. Earth and Planetary Science Letters, 397, 80–92.
[11] Condamine, P., Medard, E. Devidal, J-L. (2016). Experimental melting of flogopite-peridotite in the garnet stability field. Contributions to Mineralogy and Petrology, 171: 95.
[12] Coogan, L. A., Saunders, A. D. Wilson, R. N. (2014). Aluminum-in-olivine thermometry of primitive basalts: evidence of anomalously hot mantle source for large formations of provinces. Chemical Geology, 368, 1–10.
[13] Cook, S. J., Bowman, J. R. (2000). Mineralogical evidence for fluid-rock interaction accompanying prograde metamorphism of siliceous dolomites contact: Alta stock, Utah aureole, USA. Journal of Petrology, 41 (6), 739–757.
[14] Dasgypta, R, Hirschmann, M. M. (2007). A modified iterative sandwich method for determination of near-solidus partial melt compositions. II. Application to determination of near-solidus compositions of melt carbonated peridotite. Contributions to Mineralogy and Petrology, 154, 647–661.
[15] Di Rocco, T., Freda C., Gaeta, M., Mollo, S., Dallai, L. (2012). Magma chambers emplaced in carbonate substrate: petrogenesis of the cumulate rocks and skarn and implications for CO2 degassing in volcanic areas. Journal of Petrology, 53 (11), 2307–2332.
[16] Fumagalli, P., Poli, S. (2005). Experimentally determined phase relations in hydrous peridotites to 6.5 GPa and their consequences on the dynamics of subduction zones. Journal of Petrology, 46 (3), 555–578.
[17] Gavrilenko, M., Herzberg, C., Vidito, C., Carr, M. G., Tenner, T., Ozerov, A. (2016). A calcium-in-olivine geohygrometer and its application to subduction zone magmatism. Journal of Petrology, 57 (9), 1811–1832.
[18] Golovin, A. V., Sharygin, V. V., Pokhilenko, N. P. (2007). Melt inclusions in phenocrysts of olivine from unaltered kimberlites of the Udachnaya-Vostochnaya Pipe (Yakutia): some aspects of evolution of kimberlite magma in the later stages of crystallization. Petrology, 15 (2), 178–195.
[19] Gorbachev, N. S., Kostyuk, A. V., Shapovalov, Yu. B. (2015). Experimental study of peridotite–H2O system at P 3.8–4 GPa, T 1000–1400 °С: critical ratio and vertical zoning of the upper mantle. Doklady Akademii Nauk, 461 (4), 442–446.
[20] Gurenko, A. A, Kamenetsky, V. S., Kerr, A. S. (2016). Oxygen isotopes and volatile contents of the Gorgona komatiites, Colombia: A confirmation of the deep mantle origin of Н2O. Earth and Planetary Science Letters, 454, 154–165.
[21] Gurenko, A. A., Sobolev, A. V. (2006). Crust-primitive magma interaction beneath neovolcanic rift zone of Iceland recorded in gabbro xenoliths from Midfell, SW Island. Contributions to Mineralogy and Petrology, 151, 495–520.
[22] Gurenko, A. A., Sobolev, A. V., Kononkova, N. N. (1989). New data on petrology of uvanites of the East African Rift based on study of magmatic inclusions in minerals. Doklady Akademii Nauk, 305 (6), 1458–1463.
[23] Guzmics, T., Mitchell, R. H., Szabo, C., Berkezi, M., Milke, R., Abart, R. (2011). Carbonatite melt inclusions in coexisting magnetite, apatite and monticellite in Kerimaci calciocarbonate, Tanzania: melt evolution and petrogenesis. Contributions to Mineralogy and Petrology, 161, 177–196.
[24] Hirano, N., Ymamoto, J., Kagi, H., Ishii, T. (2004). Young, olivine xenocryst-bearing alkali-basalt from the ocean-ward slope of the Japan trench. Contributions to Mineralogy and Petrology, 148 (1), 47–54.
[25] Kamenetsky, V. S., Kamenetsky, M. B., Sobolev, A. V., Golovin, A. V., Demouchy, S., Faure, K., et al. (2008). Olivine in the Udachnaya-East kimberlite (Yakutia, Russia): types, compositions and origins. Journal of Petrology, 49 (4), 823–839.
[26] Lissenberg, C. J., Dick, H. J. B. (2008). Melt-rock reaction in lower oceanic crust and its implications for the genesis of mid-ocean ridge basalt. Earth and Planetary Science Letters, 271, 311–325.
[27] Litvin, Yu. A., Spivak, A. V., Kuzyura, A. V. (2016). Fundamentals of mantle-carbonatite concept of diamond genesis. Geochemistry, 10, 873–892.
[28] Makeev, A. B., Kriulina, G. Yu. (2012). Metal films on the surfaces and within diamond crystals from Arkhangelskaya and Yakutian diamond provinces. Zapiski Rossiiskogo Mineralogicheskogo Obshchestva, 1, 101–114.
[29] Merkulova, M., Minoz, M., Vidal, O., Brunet. (2016). Role of iron content on serpentinite dehydration depth in subduction zones: Experiment and thermodynamic modeling. Lithos, 264, 441–452.
[30] Muravieva, N. S. Senin, V. G. (2009). Carbonate-silicate equilibria in high-magnesia ultrapotassic volcanics of the Toro-Ankole province (East African rift zone). Geochemistry, 9, 937–957.
[31] Neumann, E-R., Vannucci, R., Tiepolo, M. (2005). N-MORB crust beneath Fuerteventura in the easternmost part of the Canary Islands: evidence from gabbroic xenoliths. Contributions to Mineralogy and Petrology, 150, 156–173.
[32] Neuser, R. D., Shertl, H.-P., Logvinova, A. M., Sobolev, N. V. (2015). Study of olivine inclusions in Siberian diamonds by using the method of diffraction of backscattered electrons: evidence for syngenetic growth? Geology and Geophysics, 56 (1–2), 416–425.
[33] Niida, K., Green, D. H. (1999). Stability and chemical composition of pargasitic amphibole in MORB pyrolite under upper mantle conditions. Contributions to Mineralogy and Petrology, 135, 18–40.
[34] Nikolaeva, A. T. (2014). Petrology of melilite-bearing rocks of Cupello and Colle Fabri volcanoes (Central Italy), (Doctoral Dissertation), IGM SB RAS, Novosibirsk.
[35] Palyanov, Yu. N., Sokol, A. G., Khokhryakov, A. F., Palyanova, A. G., Borzdov, Yu. M, Sobolev, N. V. (2000). Diamond and graphite crystallization from COH-fluids at PT conditions of natural diamond formation. Doklady Akademii Nauk, 375 (3), 384–388.
[36] Palyanov Yu. N., Sokol A. G., Khokhryakov A. F., Krul A. N. (2015). Conditions of diamond crystallization in kimberlite melt: experimental data. Geology and Geophysics, 56 (1), 254–272.
[37] Panina, L. I., Stopa, F., Usoltseva, L. M. (2003). Genesis of melilitites rocks of Pian di Celle volcano, Umbrian Kamafugite Province, Italy: Evidence from melt inclusions in minerals. Petrology, 11 (4), 405–424.
[38] Pirard, C., Hermann, J. (2015). Experimentally determined stability of alkali amphibole in metasomatised dunite at sub-arc pressure. Contributions to Mineralogy and Petrology, 169: 1.
[39] Plechov, P. Yu., Nekrylov, N. A., Shcherbakov, V. D., Tikhonova, M. S. (2017). Extreme-Mg olivines from venancite lavas of Pian di Celle volcano (Italy). Doklady Akademii Nauk, 474 (3), 331–335.
[40] Ponomarev, G. P. (2014a). Calcium content of olivine crystals grown from experimental melts. Part 1. Lithosphere, (4), 66–79.
[41] Ponomarev, G. P. (2014b). Calcium content in natural olivine crystals as an indicator of its genesis. Part 2. Lithosphere, (5), 57–70.
[42] Ponomarev, G. P., Puzankov, M. Yu. (2012). Distribution of the rock-forming elements in the system mafic-ultramafic melt spinel, olivine, orthopyroxene, clinopyroxene, plagioclase. Experimental evidence: geological application. Moscow: Probel.
[43] Ponomarev, G. P., Puzankov, M. Yu. (2016). Distribution of rock-forming elements in the system of melt-spinel-olivine involving aqueous fluid based on experimental data. Vestnik KRAUNTs. Earth sciences, 32 (4), 59–72.
[44] Rao, D., Misra, S., Banerjee, R., Weis, D. (2011). Geochemical investigation of gabbro from slow-spreading Northern Central Indian Ocean ridge, Indian Ocean. Geological Magazine, 148 (3), 404–422.
[45] Ryabchikov, I. D., Kogarko, L. N. (2016). Deep differentiation of alkaline-ultramafic magmas: formation of carbonatite melts. Geochemistry, 9, 771–779.
[46] Safonov, O. G., Butvina, B. G. (2013). Interaction of model peridotite with fluid H2O-KCl: experiment at pressure 1.9 GPa and its application to processes of upper mantle metasomatism. Petrology, 21 (6), 654–672.
[47] Sanfilippo, A., Dick, H. J. B., Ohara, Y. (2013). Melt-rock reaction in the mantle: mantle troctolites from the Parece Vela ancient back-arc spreading center. Journal of Petrology, 54 (5), 861–885.
[48] Sekisova, V. S., Sharygin, V. V., Zaitsev, A. N., Strekopytov, S. S. (2015). Liquid immiscibility during crystallization of forsterite-phlogopite ijolites at Oldoinyo Lengai volcano, Tanzania: study of melt inclusions. Geology and Geophysics, 56 (12), 2173–2197.
[49] Sharygin, I. S., Shatskiy, A., Litasov, K. D., Golovin, A. V., Ohtani, E., Pokhilenko, N. P. (2018). Interaction of peridotite with Ca-rich carbonatite melt at 3.1 and 6.5 GPa: implication for merwinite formation in upper mantle, and for the metasomatic origin of sublithospheric diamonds with Ca-rich suite of inclusions. Contributions to Mineralogy and Petrology, 173: 22.
[50] Shejwalkar A., Coogan L. A. (2013). Experimental calibration of the roles of temperature and composition in Ca-in-olivine geothermometer at 0.1MPa. Lithos, 177, 54–60.
[51] Silaev, V. I., Karpov, G. A., Rakin, V. I., Anikin, L. P., Vasiliev, V. A., Filippov, V. N., Petrovsky V. A. (2015). Diamonds in products of the Fissure Tolbachik eruption 2012–2013, Kamchatka. Bulletin of the Perm University (Geology), 1 (26) 6–27.
[52] Silantyev, S. A., Kostitsyn, Y. A., Cherkashin, D. V., Dick, G. J. B., Kelemen, P. B., Kononkova, N. N., et al. (2008). Magmatic and metamorphic evolution of the oceanic crust in the western flank of the MAR crest zone at 15°44′N: Investigation of cores from sites 1275B and 1275D wells (209 flight, Joides Resolution). Petrology, 16 (4), 376–400.
[53] Simkin, T., Smith, L. V. (1970). Minor-element distribution in olivine. Journal of Geology, 78 (3) 304–325.
[54] Sokol, A. G., Khokhrykov, A. F., Palyanov, Yu. N. (2015). Composition of primary kimberlite magma: constraints from melting and diamond dissolution experiments. Contributions to Mineralogy and Petrology, 170: 26.
[55] Sokol, A. G., Kruk, A. N. (2015). Conditions for generation of kimberlite magmas: review of experimental constraints. Geology and Geophysics, 56 (1–2), 316–336.
[56] Sokol, A. G., Kruk, A. N., Chebotarev, D. A., Palyanov, Y. N. (2016). Carbonate melt-peridotite interaction at 5.5-7.0 GPa: implications for metasomatism in lithosperic mantle. Lithos, 248–251, 66–79.
[57] Sokol, A. G., Kruk, A. N., Palyanov, Y. N., Sobolev, N. V. (2017). Stability of phlogopite in ultrapotassic kimberlite-like systems at 5.5–7.5 GPa. Contributions to Mineralogy and Petrology, 172: 21.
[58] Sobolev, N. V., Logvinova, A. M., Zadgenizov, D. E., Efimova, E. S., Lavrentyev Yu. G., Usova, L. V. (2000). Abnormally high content of nickel impurity in olivine inclusions from micro diamonds of Yubileinaya kimberlite pipe (Yakutia). Doklady Akademii Nauk, 375 (3), 393–396.
[59] Sobolev, A. V., Sobolev, S. V., Kuzmin, D. V., Malich, K. N., Petrunin, A. G. (2009). Mechanism of formation of Siberian meimechites and the nature of their connection with the traps and kimberlites. Geology and Geophysics, 50 (12), 1293–1334.
[60] Stoppa, F., Lipini, L. (1993). Mineralogy and petrology of the Polino monticellite calciocarbonatite (Central Italy). Mineralogy and Petrology, 49, 213–231.
[61] Suhr, G., Hellebeand, E., Jonhnson, K., Brunelli, D. (2008). Stacked gabbro units and intervening mantle: a detailed look at a section of IODP Leg 305, Hole U1309D. Geochemistry, Geophysics, Geosystems, 9 (10), 1–31.
[62] Tenner, J. T., Hirschmann, M. M., Withers, A. C., Ardia, P. (2012). Н2O storage capacity of olivine and low-Ca pyroxene from 10 to 13 GPa: consequences for dehydration melting above the transition zone. Contributions to Mineralogy and Petrology, 163, 297–316.
[63] Tornare, E., Pilet, S., Bussy, S. (2016). Magma differentiation in vertical conduits revealed by the complementary study of plutonic and volcanic rocks from Fuerteventura (Canary Islands). Journal of Petrology, 57 (11–12), 2221–2250.
[64] Willcox, A., Buismann, I., Sparks, R. S. J., Brown, R. J., Mania, S., Schumacher, J. C., Tuffen, H. (2015). Petrology, geochemistry and low-temperature alteration of lavas and pyroclastic rocks of the kimberlitic Ingwisi Hills volcanoes, Tanzania. Chemical Geology, 405, 82–101.
Cite This Article
  • APA Style

    Ponomarev Georgy, Vladykin Nikolay, Radomskaya Tatyana. (2020). Genetic Role of Calcium Content in Olivine Crystals of Ultramafic and Mafic Rocks. American Journal of Physical Chemistry, 9(2), 16-26. https://doi.org/10.11648/j.ajpc.20200902.11

    Copy | Download

    ACS Style

    Ponomarev Georgy; Vladykin Nikolay; Radomskaya Tatyana. Genetic Role of Calcium Content in Olivine Crystals of Ultramafic and Mafic Rocks. Am. J. Phys. Chem. 2020, 9(2), 16-26. doi: 10.11648/j.ajpc.20200902.11

    Copy | Download

    AMA Style

    Ponomarev Georgy, Vladykin Nikolay, Radomskaya Tatyana. Genetic Role of Calcium Content in Olivine Crystals of Ultramafic and Mafic Rocks. Am J Phys Chem. 2020;9(2):16-26. doi: 10.11648/j.ajpc.20200902.11

    Copy | Download

  • @article{10.11648/j.ajpc.20200902.11,
      author = {Ponomarev Georgy and Vladykin Nikolay and Radomskaya Tatyana},
      title = {Genetic Role of Calcium Content in Olivine Crystals of Ultramafic and Mafic Rocks},
      journal = {American Journal of Physical Chemistry},
      volume = {9},
      number = {2},
      pages = {16-26},
      doi = {10.11648/j.ajpc.20200902.11},
      url = {https://doi.org/10.11648/j.ajpc.20200902.11},
      eprint = {https://download.sciencepg.com/pdf/10.11648.j.ajpc.20200902.11},
      abstract = {The results of genetic systematization of olivine compositions formed both under experimental conditions and its natural differences from rocks of basic and ultramafic compositions of various depth facies and formed in various geodynamic settings are presented. Similar work [53], performed in the 70s of the last century and has been actively cited to this day. Generalization of the subsequent accumulated data showed the error of one of the main conclusions in this work – the dependence of the Cao content in olivine on the hydrostatic pressure during its formation from the melt. According to experimental studies conducted in recent years, up to a pressure of 29 GPA, the content of calcium in olivine, which has grown from the main-ultrabasic melts, does not depend on the pressure and is not lower than 0.1 wt.% CaO. Experiments in solidus conditions involving fluid and natural data have demonstrated that one of the leading factors affecting the calcium content in olivine are metasomatic processes that lead to the removal of calcium from olivine crystals. The role of metasomatic transformations of olivine in terms of calcium content, despite the apparent insignificance of secondary changes in it, is clearly visible in the examples of basalts and gabbro of the modern oceanic crust and the same facies differences in ophiolite complexes. The wide development of metasomatic transformations of igneous rocks of various facies and ages indicates the need to take into account the calcium content in olivine as an equilibrium criterion when calculating temperatures and pressures for paragenesis involving olivine. Olivines, which are part of ultrabasic xenoliths carried out by sub-alkaline magmas, including those carried out by kimberlites, are overwhelmingly represented by low-calcium differences. Low levels of calcium in olivines from these mantle fragments suggest that magmatic melts of the main-ultramafic compositions are not in equilibrium with the mantle substance to depths of about ~ 200 km, and possibly more. Among the compositions of olivines from fresh effusive rocks, its inclusions and microlites are mostly represented by calcium-containing differences. Only in kimberlites, almost all the differences in its crystals (inclusions, microlites) in the rock are represented by low-calcium differences. Olivines included in diamonds are also overwhelmingly represented by low calcium differences. This suggests that the composition of kimberlite olivine is associated with metasomatic transformations, and the growth of diamonds from kimberlites is due to the fluid. Inside the natural single crystals of diamond, there are polymetallic films buried in the body of crystals. Similar films were formed on the faces of diamond crystals formed in the Lav pores (that is, almost on the surface of the day) in 2012-13 of the Tolbachinsky Fissure eruption. These data allow us to create artificial "soft" conditions (CVD, solution, etc.) for the growth of single-crystal diamond films on similar polymetallic or single-element films. For these purposes, elements such as zirconium, dysprosium, erbium, and others can be used.},
     year = {2020}
    }
    

    Copy | Download

  • TY  - JOUR
    T1  - Genetic Role of Calcium Content in Olivine Crystals of Ultramafic and Mafic Rocks
    AU  - Ponomarev Georgy
    AU  - Vladykin Nikolay
    AU  - Radomskaya Tatyana
    Y1  - 2020/05/29
    PY  - 2020
    N1  - https://doi.org/10.11648/j.ajpc.20200902.11
    DO  - 10.11648/j.ajpc.20200902.11
    T2  - American Journal of Physical Chemistry
    JF  - American Journal of Physical Chemistry
    JO  - American Journal of Physical Chemistry
    SP  - 16
    EP  - 26
    PB  - Science Publishing Group
    SN  - 2327-2449
    UR  - https://doi.org/10.11648/j.ajpc.20200902.11
    AB  - The results of genetic systematization of olivine compositions formed both under experimental conditions and its natural differences from rocks of basic and ultramafic compositions of various depth facies and formed in various geodynamic settings are presented. Similar work [53], performed in the 70s of the last century and has been actively cited to this day. Generalization of the subsequent accumulated data showed the error of one of the main conclusions in this work – the dependence of the Cao content in olivine on the hydrostatic pressure during its formation from the melt. According to experimental studies conducted in recent years, up to a pressure of 29 GPA, the content of calcium in olivine, which has grown from the main-ultrabasic melts, does not depend on the pressure and is not lower than 0.1 wt.% CaO. Experiments in solidus conditions involving fluid and natural data have demonstrated that one of the leading factors affecting the calcium content in olivine are metasomatic processes that lead to the removal of calcium from olivine crystals. The role of metasomatic transformations of olivine in terms of calcium content, despite the apparent insignificance of secondary changes in it, is clearly visible in the examples of basalts and gabbro of the modern oceanic crust and the same facies differences in ophiolite complexes. The wide development of metasomatic transformations of igneous rocks of various facies and ages indicates the need to take into account the calcium content in olivine as an equilibrium criterion when calculating temperatures and pressures for paragenesis involving olivine. Olivines, which are part of ultrabasic xenoliths carried out by sub-alkaline magmas, including those carried out by kimberlites, are overwhelmingly represented by low-calcium differences. Low levels of calcium in olivines from these mantle fragments suggest that magmatic melts of the main-ultramafic compositions are not in equilibrium with the mantle substance to depths of about ~ 200 km, and possibly more. Among the compositions of olivines from fresh effusive rocks, its inclusions and microlites are mostly represented by calcium-containing differences. Only in kimberlites, almost all the differences in its crystals (inclusions, microlites) in the rock are represented by low-calcium differences. Olivines included in diamonds are also overwhelmingly represented by low calcium differences. This suggests that the composition of kimberlite olivine is associated with metasomatic transformations, and the growth of diamonds from kimberlites is due to the fluid. Inside the natural single crystals of diamond, there are polymetallic films buried in the body of crystals. Similar films were formed on the faces of diamond crystals formed in the Lav pores (that is, almost on the surface of the day) in 2012-13 of the Tolbachinsky Fissure eruption. These data allow us to create artificial "soft" conditions (CVD, solution, etc.) for the growth of single-crystal diamond films on similar polymetallic or single-element films. For these purposes, elements such as zirconium, dysprosium, erbium, and others can be used.
    VL  - 9
    IS  - 2
    ER  - 

    Copy | Download

Author Information
  • Laboratory of Petrology and Goechemistry, Institute of Volcanology and Seismology FEB RAS, Petropavlovsk-Kamchatsky, Russia

  • Laboratory of Geochemistry and Alkaline Rocks, Vinogradov Institute of Geology SB RAS, Irkutsk, Russia

  • Laboratory of Geochemistry and Alkaline Rocks, Vinogradov Institute of Geology SB RAS, Irkutsk, Russia

  • Section