Identifying mantle carbonatite metasomatism through Os–Sr–Mg isotopes in Tibetan ultrapotassic rocks
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چکیده
منابع مشابه
Carbonatite Metasomatism in the Southeastern Australian Lithosphere
New mineralogical and geochemical data from a suite of glass ± from the mantle (Deines & Gold, 1973; Nelson et al., 1988). However, controversy remains as to whether such apatite ± amphibole ± phlogopite ± carbonate-bearing spinel magmas represent (1) direct partial melts of carbonatewehrlite, lherzolite and harzburgite xenoliths from the Newer Volbearing mantle peridotite (i.e. primary carbona...
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The Piquiri Syenite Massif, southernmost Brazil, is part of the post-collisional magmatism related to the Neoproterozoic Brasiliano-Pan-African Orogenic Cycle. The massif is about 12 km in diameter and is composed of syenites, granites, monzonitic rocks and lamprophyres. Diopside-phlogopite, diopside-biotite-augite-calcic-amphibole, are the main ferro-magnesian paragenesis in the syenitic rocks...
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Modern plate tectonic brings down oceanic crust along subduction zones where it either dehydrates or melts. Those hydrous fluids or melts migrate into the overlying mantle wedge trigerring its melting which produces arc magmas and thus additional continental crust. Nowadays, melting seems to be restricted to cases of young (< 50 Ma) subducted plates. Slab melts are silicic and strongly sodic (t...
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Analysis of data on micro- and nano-inclusions in mantle-derived and metamorphic diamonds shows that, to a first approximation, diamond-forming medium can be considered as a specific ultrapotassic, carbonate/chloride/silicate/water fluid. In the present work, the processes and mechanisms of diamond crystallization were experimentally studied at 7.5 GPa, within the temperature range of 1,400-1,8...
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ژورنال
عنوان ژورنال: Earth and Planetary Science Letters
سال: 2015
ISSN: 0012-821X
DOI: 10.1016/j.epsl.2015.09.005