Инд. авторы:	Surkov N.V., Gartvich Y.G.
Заглавие:	Physicochemical model for the crystallization of rocks of the calc-alkaline series
Библ. ссылка:	Surkov N.V., Gartvich Y.G. Physicochemical model for the crystallization of rocks of the calc-alkaline series // Geochemistry International. - 2012. - Vol.50. - Iss. 10. - P.799-815. - ISSN 0016-7029. - EISSN 1531-8397.
Внешние системы:	DOI: 10.1134/S0016702912100060; SCOPUS: 2-s2.0-84866939480;
Реферат:	eng: The Al-rich region of the CaO-MgO-Al 2O 3-SiO 2 system was experimentally studied at pressures of 1. 0-2. 8 GPa and temperatures of 1300-1535°C. The slopes of the lines of the monovariant reactions An + Sp = Cpx + Cor + (Ga) and L = Cpx + Ga + Cor + Sp and the compositions of the phases involved in these reactions are determined. The results are utilized in the topological analysis of the aluminous region of the CaO-MgO-Al 2O 3-SiO 2 system. On this basis, the principal structure of the phase diagram is analyzed, and a phase diagram is constructed for the junction region of the quaternary system and the CaO-Al 2O 3-SiO 2 ternary system. A continuous series of the monovariant eutectic: L = Cpx + Opx + Fo + An, L = Cpx + Opx + An + Sp, L = Cpx + (Ga) + An + Sp, L = Cpx + Cor + (Ga) + An, L = An + Ga + Cpx + Ky and L = Ga + Cpx + Ky + Qz is examined within the pressure range from atmospheric to 3. 0 GPa and higher. Analogous 'telescoped' eutectic series are of fundamental character for interpreting the evolution of magmatic melts. A physicochemical model is suggested for the evolution of magmatic melts that produce rocks of the calc-alkaline series, with this model underlain by the fact that a change in the composition of magmatic melt at a pressure decrease should correspond to the minimum melting temperatures, i. e., to melts in the fundamental series of eutectic reactions. The comparison of our physicochemical model and rocks of the calc-alkaline series shows that the compositions of rocks of the calc-alkaline series are close to the compositions determined for the eutectic equilibria, and the mineralogical composition of xenoliths and megacrysts in volcanic and dike varieties of the rocks are similar to the subsolidus phases of the established fundamental eutectic system. © 2012 Pleiades Publishing, Ltd.
Ключевые слова:	eclogitization reaction; eutectic; physicochemical property; pressure effect; silicon; temperature effect; topology; xenolith; volcanic rock; mineralogy; megacryst; magnesium; magma; lime; igneous rock; igneous geochemistry; experimental study; eclogite; dike; crystallization; chemical composition; atmospheric pressure; aluminum oxide; Rocks; Volcanic rocks; Phase diagrams; Hydraulic structures; Gallium; Eutectics; Aluminum; monovariant reactions; Magma evolution; Invariant equilibria; eclogitization reaction; Calc-alkaline rocks; phase diagram; monovariant reactions; magma evolution; calc-alkaline rock series; invariant equilibrium;
Издано:	2012
Физ. характеристика:	с.799-815