DIFFUSION, REACTION AND FLOW PHENOMENA RELATED TO PATTERN FORMATION IN ROCKS

(1)蛇形底辟的模拟出现在伊豆-小asawara- Mariana前弧的蛇形海山被模拟为来自楔形地幔的蛇形底辟。在观测和模拟的基础上，讨论了海山发育的时空尺度。假定由于SiO2和H2O的扩散供应，楔状地幔底层发生蛇纹石化。利用底辟形成理论，根据底辟间距与蛇纹岩与地幔黏度比的关系，估计蛇纹岩层厚度约为10米左右。(2)花岗质体系熔融实验及花岗质熔体扩散系数测量。在花岗岩体系中进行了共晶点以上温度下的非平衡熔融实验，模拟了混杂岩的自然熔融现象。在钠长石单晶和石英粉等熔融偶体之间形成薄的熔体层。熔体层厚度服从抛物线型增长规律，表明熔体层的增长受扩散限制。最慢组分（速率决定组分）的扩散系数由抛物线增长速率定律估计。

(1) Modeling of serpentine diapirSerpentine seamounts which occur in the Izu - Ogasawara- Mariana forearcs are modeled as serpentine diapir from the wedge mantle. The time and space scale of the development of seamounts were discussed based on observations and modeling. Serpentinization of the bottom layer of the wedge mantle due to diffusive supply of SiO2 and H2O is assumed. The thickness of the serpentinized layer is estimated to be the order of 10 meters by employing theory of diapir formation using the relation between the spacing of diapirs and viscosity ratio of serpentinite and the mantle.(2) Melting experiments in granitic system and measurements of diffusion coefficients in the granitic melts.Non-equilibrium melting experiments at temperatures above the eutectic point were carried out in granitic system to simulate natural melting phenomena in migmatite experimentally. Thin melt layers were formed between melting couples such as albite single crystal and quartz powder. The thickness of the melt layer obeys the parabolic growth rate law, suggesting diffusion limited growth of the layer. Diffusion coefficient of the slowest component (rate - determining component ) is estimated by the parabolic growth rate law.