Тип публикации: статья из журнала
Год издания: 2017
Идентификатор DOI: 10.1007/s00710-016-0477-8
Ключевые слова: Brucite marble, Decarbonation, Fluid depleted in C13, Fluid-rock interaction, Olkhon collision system, Skarn, Stable isotopes, Tazheran gabbro-syenite massif
Аннотация: Stable isotope compositions are examined for brucite marble and Mg-skarn that occur in the southern part of the Tazheran massif, Olkhon region, Russia. Brucite marble exhibits a narrow range in δ18O of +23.3 to +26.2 ‰ and shows carbon isotope depletion of −1.9 to −4.4 ‰) as compared with the country dolomite isotope compositions (Показать полностью+2.0 to +2.4 ‰) which is explained by both decarbonation processes and participation of fluids depleted in 13C. The emplacement of brucite marble was accompanied by the formation of endo- and exoskarn at the contact between syenite and brucite marble. δ18O profiles across the contact show a typical decrease towards the syenite side interpreted as the result of fluid/rock interaction and influx of magmatic fluids. Finally, we discuss the mechanisms of brucite marble emplacement and consider three possible ways of producing these rocks: (1) injection of dolomite with subsequent transformation to periclase marble and then to brucite marble; (2) injection of periclase marble with a following replacement of periclase by brucite or injection of brucite marble; (3) crustal water-rich carbonate melt. We favor models 2 and 3 and discuss their strengths and weaknesses. © 2016, Springer-Verlag Wien.
Журнал: Mineralogy and Petrology
Выпуск журнала: Vol. 111, Is. 3
Номера страниц: 399-416
ISSN журнала: 09300708
Издатель: Springer-Verlag Wien