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本文采用石英和人工合成长石的混合物配制成的原料在P_(H2O)=2～15千巴的压力范围内进行了Qz-Or-Ab-H_2O体系初熔的反演。在无钙长石的碱性长石花岗岩体系Qz-Or-Ab-H_2O中,其熔融温度随着增压,从2千巴时的690℃降低到17千巴时的630℃。在花岗岩体系Qz-Or-Ab-An-H_2O中,随着钙长石含量的增加其固相线温度的升高是非常小的。与碱性长石花岗岩体系相比较,如果钠长石被斜长石An20(An40)代替,其固相线温度升高3℃(7°D)。碱性长石花岗岩体系和石英—钙长石—透长石组合(Qz-Or-An-H_2O体系)的固相线温度间的差别接近50℃。随着水压增高,斜长石及斜长石—碱性长石组合就变得不稳定,并分别被黝帘石+蓝晶石+石英和黝帘石+白云母-钠云母_(固溶体)+石英代替。并发现这些组合的压力稳定范围在600℃时介于6和16千巴之间。在高水压条件下(10～18千巴)。黝帘石-白云母-石英组合稳定到700和720℃。这个组合的固相线在透长石-黝帘石-白云母-石英混合物开始熔融温度以上10～20℃。为产生足够量的熔体,把变质岩变成岩浆岩状的岩石所需要水量只是非常少的。在层状混合岩的情况下证明,1％的水(或甚至更少)就足以使片麻岩局部转变为(岩浆状的)浅色部分,高级变质岩石或许是比较干的,而花岗岩质和花岗闪长岩质成分的重熔岩浆通常处于水不饱和状态。
In this paper, the initial melting of the Qz-Or-Ab-H_2O system was carried out in the pressure range of P_ (H2O) = 2 ~ 15 kPa by using the mixture of quartz and synthetic feldspar. In Qz-Or-Ab-H 2 O, a feldspar-rich alkaline feldspar granite system, its melting temperature decreases from 690 ° C at 2 kPa to 630 ° C at 17 kPa with increasing pressure. In the Qz-Or-Ab-An-H_2O granitic system, the increase of solidus temperature with the increase of the content of anorthite is very small. In contrast to the alkaline feldspar granite system, if the albite is replaced by An20 (An40), the temperature of the solidus increases 3 ° C (7 ° D). The difference between the solidus temperatures of the alkaline feldspar granite system and the quartz-and-feldspar-periclase combination (Qz-Or-An-H 2 O system) is close to 50 ° C. As the water pressure increases, the plagioclase and plagioclase-alkaline feldspar assemblages become unstable and are replaced by zoisite + kyanite + quartz and zoisite + muscovite-mica (solid solution ) + Quartz instead. The pressure stability of these combinations was found to be between 6 and 16 kPa at 600 ° C. Under high water pressure conditions (10-18 bar). The zoisite-muscovite-quartz combination stabilized to 700 and 720 ° C. The solidus of this combination is at a temperature of 10 to 20 ° C above the melting temperature of the Peridot-Zoisite-Muscovite-Quartz mixture. In order to produce a sufficient amount of melt, the amount of water needed to turn metamorphic rocks into magmatic rocks is very small. In the case of stratified migmatites it turns out that 1% of the water (or even less) is sufficient to locally transform the gneiss into a (magmatic) light-colored part, the higher metamorphic rocks may be drier and the granitic The reclaimed magma, together with the granodiorite components, is usually in a water-unsaturated state.