| Инд. авторы: | Bazhan I.S., Ozawa S., Miyahara M., Ohtani E., Litasov K.D. |
| Заглавие: | “Spherulite-like” jadeite growth in shock-melt veins of the Novosibirsk H5/6 chondrite |
| Библ. ссылка: | Bazhan I.S., Ozawa S., Miyahara M., Ohtani E., Litasov K.D. “Spherulite-like” jadeite growth in shock-melt veins of the Novosibirsk H5/6 chondrite // Russian Geology and Geophysics. - 2017. - Vol.58. - Iss. 1. - P.12-19. - ISSN 1068-7971. - EISSN 1878-030X. |
| Внешние системы: | DOI: 10.1016/j.rgg.2016.04.012; SCOPUS: 2-s2.0-85013188747; WoS: 000395217700002; |
| Реферат: | eng: The Novosibirsk H5/6 ordinary chondrite has signs of shock metamorphism, such as dark shock-melt veins (SMVs) crossing the chondrite host rock. The plagioclase composition grains (Ab78An14Or7) with jadeite were found in the host-rock fragments inside the SMVs. Jadeite has an unusual radial-concentric spherulite-like microtexture. The spherulite-like jadeite formed from the molten plagioclase grain under high-pressure and high-temperature conditions during an impact event. The crystallization was accompanied by sodium-potassium differentiation between coexisting jadeite and residual melt. The PT-conditions of jadeite formation were estimated to be 3-14 GPa and 1400-2150 °C. Jadeite crystallization, Na-K differentiation, and the pressure-temperature estimates of jadeite formation in the Novosibirsk chondrite are very close to those in the Chelyabinsk LL5 chondrite. The spherulite-like microtexture and jadeite-glass coexistence, most likely, point to a high cooling rate of the SMVs at the pressure release stage of the metamorphic process. © 2017
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| Ключевые слова: | spherulite-like microtexture; shock metamorphism; plagioclase melt; Novosibirsk H5/6 chondrite; jadeite; |
| Издано: | 2017 |
| Физ. характеристика: | с.12-19 |