RESEARCH ON THE EFFECT OF GRAIN-SEE OF MINERALS ON METAMORPHIC REACTIONS

过去我们无法直接获得深部地壳和地幔的物理化学条件，但深部形成的变质岩却为我们提供了大量的信息来估计其形成条件。组成矿物的种类和化学成分取决于温度和压力等物理条件，而矿物的粒度则受热活化过程控制，如颗粒膨胀迁移和成核生长。这两个方面密切相关，尽管每一个观点都被分为岩石学和构造地质学。为了更好地了解地球表面下矿物和岩石的物理化学行为，需要将这两门学科结合起来。本研究旨在确定世界上几个变质区岩石的物理条件和运动学参数，包括日本西南部的Ryoke变质岩，日本西南部的Dalradian变质岩， 关于我们 苏格兰和南极洲东部的Lutzow-Holm复合体。几篇论文在以下几个方面对地壳深部的认识有所贡献：Ryoke变质作用的变质相属于麻粒岩相，而不是以前认为的角闪岩相。指出了吉布斯方法在低压变质岩中应用时应注意的几个问题。提出了一种新的压力估算方法，并将其应用于Ryoke变质岩中。结果较以往更精确地反映了变质区的温压结构。从共生稳定性方面评价了组成矿物中微量元素的作用。硼对上地壳部分熔融的重要性在Ryoke变质岩中得到了揭示。本文以南极高温变质岩为例，讨论了高温变质岩测温的局限性。Lutzow-Holm杂岩的区域结构特征。通过岩石学、矿物学和构造分析，揭示了变质矿物的形态和粒度变化。这些信息使我们能够讨论矿物在变形介质中的各向异性生长。少

We can not obtain information directly on physical and chemical conditions of the deeply seated crust and mantle in the past, however, the metamorphic rocks formed in a depth provide us numerous information to estimate conditions of its formation. Species and chemical composition of constituent minerals depend on the physical conditions such as temperature and pressure, whereas grain-size of minerals is controlled by thermally activated processes such as grain boudary migration and nucleation-and-growth. These two aspects closely relate each other, even though each view point has been divided into petrology and structural geology. Combination of the two subjects are required to understand physical and chemical behaviour of minerals and rocks beneath the Earth's surface.This study intended to determine physical conditions and kinematic parameters of rocks from several metamorphic regions in the world, including the Ryoke metamorphic rocks in SW Japan, the Dalradian metamorphic rocks in … More Scotland and the Lutzow-Holm Complex in East Antarctica. Several papers contributed to progress the understanding of the deep crust in the following aspects.Metamorphic facies of the Ryoke metamorphism belongs to the granulite facies, contrary to the previous understanding as amphibolite facies. Several problems were pointed out to applying the Gibbs method to low-pressure metamorphic rocks. A new technique to estimate pressure was proposed, and was applied to the Ryoke metamorphic rocks. The results show the thermobaric structure of the metamorphic region more precisely than before. The effect of minor elements in constituent minerals was evaluated with respect to the paragenetic stability. The importance of boron for the partial melting of upper crust was revealed in the Ryoke metamorphic rocks. Limit of geothermometry for high-temperature metamorphic rocks was discussed using samples from the Antarctica. Regional structure of the Lutzow-Holm Complex was characterized. Change in shape and grain-size of metamorphic minerals was revealed based on petrological, mineralogical and structural analyses. This information enabled us to discuss the anisotropic growth of mineral in a deforming media. Less