Melting phase relations of natural peridotite +CO 2 as a function of degree of partial melting at 15 and 30 kbar

摘要: Phase relations of peridotite * CO, have been determined at 15 and 30 kbar using rtiW to monitor the degree melting. At initial 5 percent melt (-1400'C), where melting (to -20 melt) is nearly invariant. In this latter interval, coexisting with olivine, orthopyroxene, clinopyroxene, vapor tholeiitic. Melting coillmences more than 200oC lower for both CO2-saturated COr-undersaturated conditions. Again, exact nature interval from solidus about uncertain because presence small amounts HrO in experimental charges. Dolomite a phase together garnet, carbonatitic, as evidenced by quenching carbonate. With increasing partial compositions become richer silicate components, mixtures glass carbonate minerals. These results indicate that principal i1 simple systems such CaOMgO-SiOr-CO, apply natural peridotite. Published system show great depression ofthe temperature (-150"C) pressure raised above carbonation reaction. Di+Fo+VCEn*Dol same time, liquid composition changes haplobasalt haplocarbonatite therefore serves suitable model liquids produced + CO2.