Chromian Spinel from Dunites of the Inagli Massif and Their Oxygen Thermobarometry (Aldan Shield, Siberian Platform)

• Autorzy: Okrugin Alexander

Identyfikatory

DOI

10.29227/IM-2024-01-16

Warianty tytułu

PL

Spinel chromianowy z dunitów masywu Inagli i ich termobarometria tlenowa (tarcza ałdańska, platforma syberyjska)

• Języki publikacji: EN

Abstrakty

EN

The Inagli dunite-peridotite-shonkinite zonal-ring intrusive with platinum-chromite mineralization is located on the Aldan shield of the Siberian Platform. Considering the structure, rock composition and ore mineralization, it is similar to the platinum-bearing zonal massifs of the "Ural-Alaskan" type, but this intrusive differs from the latter in its geological position. In order to clarify the physical and chemical conditions of formation of the Inagli massif, the mineral composition of rocks, especially сhromite-containing dunites, peridotites and shonkinites, as well as platinum-chromitite ore segregations, has been studied in detail. The rocks of the Inagli massif, from dunites to shonkinites, including peridotites, clinopyroxenites, and alkaline syenites, form a single continuous series. This is confirmed by a clear dependence of the composition of olivine, pyroxene, phlogopite and chromian spinel on the content of MgO in rocks. They were formed from the initial high-potassium picrite melt, which, during rising, underwent gradual decompression solidification and formed a cylindrical diapir-like body at the near-surface level in the Early Cretaceous. This occurred as a result of subduction processes related to the formation of the MongolOkhotsk orogenic belt along the southern framing of the Siberian craton. The values of oxygen volatility (lgfO2) for dunites, peridotites, shonkinites, chromitites and olivine-chromite inclusions in the isoferroplatinum of the Inagli massif, calculated using the method of the olivine-spinel oxygen thermobarometer of Ballhaus-Berry-Green (BBG), form a single trend FMQ+(2-4) in the range 620-11400C, i.e. along the band by 2-4 units of lgfO2 exceeding the fayalite-magnetite-quartz (FMQ) buffer. Such a rather narrow range of variation in the values of O2 fugacity in a wide interval of temperature indicates good comparability and reliability of the data obtained. At the same time, there is a natural decrease in temperature intervals for the formation of olivine-chromite parageneses (in 0С): with isoferroplatinum – (1140-680); in chromitite segregations – (980-710); in dunites – (930-620); peridotites – (890-770) and shonkinites – (840-710). The results obtained almost completely coincide with the field of values for dunites and chromitites from the Platinum-bearing belt of the Urals, given by other researchers. In terms of redox parameters, platinum-bearing zonal ultramafic-mafic massifs of the Ural-Alaskan and Aldanian types are close to more oxidized peridotites with a long history in the lithosphere. They differ significantly from the peridotites of the Beni-Bousera massif, as well as abyssal peridotites of the oceanic ridge systems, and others, which are formed under more reduced conditions corresponding to the range between FMQ, carbon-oxygen-CO (ССО) and ironwustite (IW) buffers.

Słowa kluczowe

EN

chromian spinel; dunites of the inagli massif; oxygen thermobarometry; Siberian platform

PL

spinel chromianowy; termobarometria tlenowa; Syberia

• Wydawca: Polskie Towarzystwo Przeróbki Kopalin
• Czasopismo: Inżynieria Mineralna
• Rocznik: 2024
• Tom: Vol. 1, no. 1
• Strony: 135--144
• Opis fizyczny: Bibliogr. 25 poz., rys., tab., wykr.

Twórcy

autor

Okrugin Alexander

• Diamond and Precious Metal Geology Institute, Siberian Branch, Russian Academy of Sciences (DPMGI SB RAS), 39 Lenin Str, Yakutsk, 677980, Russia

• https://orcid.org/0000-0002-1248-8993

Bibliografia

• 1. I.S. Rozhkov. V.I. Kitsul. L.V. Razin. S.S. Borishanskaya. Platinum of the Aldan Shield (Publishing House of Academy of Sciences USSR. Moscow. 1962).
• 2. A.M. Korchagin. The Inagli Pluton and Its Mineral Resources (Nedra. Moscow. 1996).
• 3. C. Ballhaus. R.F. Berry. D.H. Green. “High pressure experimental calibration of the olivineorthopyroxene-spinel oxygen geobarometer: implication for the oxidation state of the upper mantle”. Contributions to Mineralogy and Petrology 107. 27–40 (1991).
• 4. A.V. Okrugin. A.S. Borisenko. A.I. Zhuravlev. A.V. Travin. “Mineralogical. geochemical. and age characteristics of the rocks of the Inagli dunite–clinopyroxenite–shonkinite massif with platinum–chromite and Cr-diopside mineralization (Aldan Shield)”. Russian Geology and Geophysics 59. 1301–1317 (2018).
• 5. A.V. Okrugin. “Crystallization–liquation model of formation of PGE–chromite ores in mafic–ultramafic complexes”. Tikhookeanskaya Geologiya 23. 63–75 (2004).
• 6. G.I. Khudyakov. A.P. Kulakov. B.V. Ezhov. Morphotectonic CentralType Systems in Siberia and the Far East (Nauka. Moscow. 1988).
• 7. O. Yakubovich. A. Mochalov. A. Kotov. S. Sluzhenikin. A. Okrugin. M. Daniík. B. McDonald. N. Evans. B. Mclnnes. “190Pt–4He dating of platinum mineralization.” in: Mineral Resources in a Sustainable World. Proc. 13th SGA Biennial Meet.. 24–27 August 2015. (Nancy. France. 2015) pp. 663–664.
• 8. A. Okrugin. A. Zhuravlev. O. Yakubovich. “Geodinamic setting for formation of the mesozoic au-pt deposits of the Aldan shield.” in Geology and mineral resources of the North-East of Russia: materials of the X All-Russian Scientific and practical conference. (NEFU Publishing House. Yakutsk. 2020) pp. 266-272.
• 9. A.P. Krivenko. “Mesozoic Potassic Picritoids of Central Aldan”. Doklady Akad. Nauk SSSR 254. 465–467 (1980). 10. V.S. Shkodzinskii. Global Petrology according to Modern Data on the Hot Heterogeneous Accretion of the Earth (Publishing House of SVFU. Yakutsk. 2018).
• 11. A.Ya. Kochetkov. “Mesozoic gold-bearing ore magmatic systems of Central Aldan”. Russian Geology and Geophysics 47. 850-864 (2006).
• 12. E.P. Maximov. V.I. Uyutov. V.M. Nikitin. “The Central Aldan gold-uranium ore magmatogenic system (Aldan-Stanovoy shield. Russia)”. Tikhookeanskaya Geologiya 29. 3–26 (2010).
• 13. L.M. Parfenov. L.I. Popeko. O. Tomurtogoo. “Problems of the tectonics of the Mongol–Okhotsk orogenic belt”. Tikhookeanskaya Geologiya 19. 24–43 (1999).
• 14. R.G. Yazeva. V.V. Bochkarev. “Ural platinum-bearing belt and Tagil paleoarс: magmatism and geodynamie relations”. Geotectonics. No. 2. 75-86 (2003).
• 15. V.R. Shmelev. “Magmatic complexes of a Main Urals fault zone (Prepolar sector) in light of new geochemical datas”. Litosfera. No. 2. 41-59 (2005).
• 16. J.R. Lang and T. Baker. “Intrusion-related gold systems: the present level of understanding”. Mineralium Deposita 36. 477-489 (2001).
• 17. M. Economou-Eliopoulos. “PGE potential of porphyry deposits”. in Exploration for deposits of platinum-group elements. (Mineral. Association of Canada Short Course 35. Oulu. 2005). pp. 203-245.
• 18. I.S. Chashukhin. S.L. Votyakov. E.V.Pushkarev et al.. “Oxythermobarometry of ultramafic platinumbearing belt of the Urals”. Geochemistry No. 8. 846–863 (2002).
• 19. A. Woodland. J. Kornprobst. B. Wood. “Oxygen thermobarometry of orogenic lherzolite massifs”. Journal of Petrology 33. 203-230 (1992).
• 20. L.T. Brindzia. B.J. Wood. “Oxygen thermobarometry of abyssal spinel peridotites: the redox state and C–O–H volatile composition of the Earth’s sub-oceanic upper mantle”. Am. J. Sci. 290. 1093-1116 (1990).
• 21. R I.J. Parkinson and J.A. Pearce. “Peridotites from the Izu–Bonin–Mariana Forearc (ODP Leg 125): Evidence for Mantle Melting and Melt–Mantle Interaction in a Supra-Subduction Zone Setting”. Journal of Petrology 39. 1577–1618 (1998).
• 22. R.G. Schwab. D. Küstner. “Die Gleichgewichtsfugazitaten technologisch und petrologisch wichtiger Sauerstoffpuffer”. Neues Jahrb Mineral Abh. 140. 111-142 (1981).
• 23. H.St.C. O'Neill. “The quartz-fayalite-iron and quartz-fayalite-magnetite equilibria and the free energies of formation of fayalite (Fe2SiO4) and magnetite (Fe3O4)”. Am. Mineral. 72. 67-75 (1987).
• 24. S. Jakobsson. N. Oskarsson. “The system C-O in equilibrium with graphite at high pressure and temperature: an experimental study”. Geochimica et Cosmochimica Acta 58. 9-17 (1994).
• 25. D.J. Frost. C.A. McCammon. “The redox state of Earth’s mantle”. Annu. Rev. Earth Planet. Sci. 36. 389-420 (2008)