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和化学条件信息，但是，在一定深度形成的变质岩为我们估计其形成条件提供了大量信息。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，而矿物的粒度则受晶界迁移和成核生长等热活化过程的控制。这两个方面是紧密联系在一起的，尽管每个观点都被分为岩石学和构造地质学。这两门学科的结合需要了解地球表面下矿物和岩石的物理和化学行为。本研究旨在确定世界上几个变质岩区的岩石物理条件和运动学参数，包括日本西南部的Ryoke变质岩、苏格兰…More的Dalradian变质岩和南极洲东部的Lutzow-Holm杂岩。几篇论文在以下几个方面促进了对深部地壳的认识。里奥克变质岩的变质相属于麻粒岩相，与以往认识的角闪岩相相反。指出了吉布斯方法应用于低压变质岩的几个问题。提出了一种新的压力估算方法，并将其应用于辽轭变质岩。结果比以往更精确地显示了变质区的热压结构。对组成矿物中微量元素对共生稳定性的影响进行了评价。在黎奥克变质岩中揭示了硼对上地壳部分熔融作用的重要性。以南极洲的高温变质岩样品为例，讨论了高温变质岩的测温极限。Lutzow-Holm复合体的区域结构特征。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变形介质中矿物的各向异性生长。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