Study on high- and ultrahigh- temperature metamorphic rocks and partial melting, with a point of view of quartz occurrence

砂质和泥质岩石是SiO2饱和岩石。在部分熔融过程中，石英产状和硅饱和指数是重要的影响因素。然而，石英的模态组成被忽略作为平衡计算的过量组分。本研究的目的是从石英产状的角度，通过阴极发光（CL）图像分析变质、部分熔融和花岗岩熔体分离的时间，取得了创新性的成果。在麻粒岩、混合岩、英云闪长岩中发现了较老阶段的锆石核，是沉积物的残留物。这些一定是残留的泥沙颗粒。而亮边则是部分熔融形成的新生长体。我们的研究结果改变了日高变质带的构造历史，即：（1）主热事件不是55Ma。这是两次，37Ma和19Ma。(2)37Ma为岛弧型岩浆活动。(3)19Ma是与弧后盆地开启有关的又一次岩浆活动。这一阶段为MORB型活动和麻粒岩相高温变质作用。化学发光探测器是这一新发现不可或缺的一部分。

Psammitic and pelitic rocks are SiO2 saturated rocks. On the partial melting process, quartz occurrence and silica saturation index are the important factors. However, modal composition of quartz is ignored as an excess component for the equilibrium computation. The purpose of this study is, analysis of timing of metamorphism, partial melting, and granitic melt separation, by the cathodoluminescence (CL) image, with a point of view of quartz occurrence.This project made innovative results. These are, we had found out older stage cores of zircon in the granulite, migmatite, tonalite, are residual material of the sediment. These must be residual grain of sediment. Whereas we also found out that bright rims is the new growth pert by the partial melting. We also revealed the age of the bright rims.Our results changed the tectonic history of the Hidaka Metamorphic Belt.These are:(1) Main thermal event is not 55Ma. That was two times, 37Ma and 19Ma.(2) 37Ma is island-arc type igneous activity.(3) 19Ma is another igneous activity related by back-arc basin opening. This stage is the MORB-type activity and the granulite facies high-temperature metamorphism.Our result was published by "Geology", and also newspapers. The CL detector was indispensable item for the new discovery.