| Инд. авторы: | Nikolenko E.I., Sharygin I.S., Alifirova T.A., Korsakov A.V., Zelenovskiy P.S., Shur V.Y. |
| Заглавие: | Graphite-bearing mineral assemblages in the mantle beneath Central Aldan superterrane of North Asian craton: combined confocal micro-Raman and electron microprobe characterization |
| Библ. ссылка: | Nikolenko E.I., Sharygin I.S., Alifirova T.A., Korsakov A.V., Zelenovskiy P.S., Shur V.Y. Graphite-bearing mineral assemblages in the mantle beneath Central Aldan superterrane of North Asian craton: combined confocal micro-Raman and electron microprobe characterization // Journal of Raman Spectroscopy. - 2017. - Vol.48. - Iss. 11. - P.1597-1605. - ISSN 0377-0486. - EISSN 1097-4555. |
| Внешние системы: | DOI: 10.1002/jrs.5163; РИНЦ: 31024929; WoS: 000416235800030; |
| Реферат: | eng: Mantle-derived lherzolitic and harzburgitic Cr-pyropes from lamprophyres of the Chompolo field (Central Aldan superterrane, North Asian Craton) were studied using micro-Raman spectroscopy and electron microprobe microanalysis. These garnets enclose graphite coexisting with forsterite, diopside, Ba-Cl-phlogopite, tschermakite, rutile, magnesiochromite, Mg-ilmenite, apatite, chalcopyrite, dolomite, magnesite and lindsleyite inclusions. The PT conditions of residence of graphite-bearing assemblage in the mantle were estimated, using a combination of mineral thermometers and barometers, to be as high as 2.87-3.55GPa and 710-770 degrees C. Generally, graphite within inclusions is well ordered; D1 and D2 disordered bands in its spectra are restricted to inclusion edges. The residual pressure up to 2.1GPa was inferred for graphite assuming pressure dependence of the G-band upshift (1580cm(-1) at ambient conditions vs 1588.6cm(-1) at 2.1GPa). Disordered graphite most likely appears due to the stress-induced distortion of the fully ordered graphite crystal structure. The distortion results from difference in the thermoelastic properties of graphite inclusions and their garnet hosts exposed to decompression during ascent to the surface with lamprophyre magma. The mineralogy of inclusions in the studied garnets strongly suggests an episode(s) of metasomatism by carbon-rich agent(s) (COH-fluid or carbonatitic melt) in the lithospheric mantle of the Central Aldan superterrane, which was coeval with the formation of graphite inclusions and the host pyropes. Copyright (c) 2017 John Wiley & Sons, Ltd.
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| Ключевые слова: | deep carbon cycle; mantle; PRESSURE METAMORPHIC ROCKS; DIAMOND; CARBON; DEEP MANTLE; graphite; EARTHS INTERIOR; RESIDUAL PRESSURE; PERIDOTITE MASSIF; SIBERIAN CRATON; LITHOSPHERIC MANTLE; craton; PHASE-RELATIONS; carbonate; |
| Издано: | 2017 |
| Физ. характеристика: | с.1597-1605 |