Electrical Conductivity of Olivine-Synthetic Melt Rock

该项目将对多晶橄榄石+硅酸盐熔融岩的电导率进行实验室实验研究，以阐明在部分熔融岩石中控制电导率的重要变量，并将电导率测量的外推限制到地球深部。简化部分熔融地幔岩石的合成类似物将用于系统地研究电导率对熔体分布的依赖，作为温度、氧逸度和交流频率的函数。熔体分布和电导率对熔体体积和熔体-固体系统界面能变化的敏感性将通过在固定温度和氧活度下独立改变熔体分数和熔体成分来评估。通过随后研究温度和氧逸度变化对频率响应的影响，电导率也将用于测量熔体迁移、平衡和离子扩散的动力学。电子显微镜观察将电结果与样品的结构变化联系起来。* * * *

9315935 Wanamaker The PI will perform an experimental laboratory investigation of the electrical conductivity of polycrystalline olivine plus silicate melt rocks to elucidate the variables important in controlling conductivity in partially molten rocks and to constrain extrapolation of conductivity measurements to the deep earth. Synthetic analogues of simplified partially molten mantle rocks will be used to study systematically the dependence of electrical conductivity on melt distribution as a function of temperature, oxygen fugacity, and a.c. frequency. The sensitivity of melt distribution, and thus conductivity, to changes in volume of melt and the interfacial energies of the melt-solid system will be assessed by independently varying both the melt fraction and melt composition at fixed temperature and oxygen activity. By subsequently investigating the effect of changes in temperature and oxygen fugacity on the frequency response, electrical conductivity will also be used to measure the kinetics of melt migration, equilibration, and ionic diffusion. Electron microscopy observations will link the electrical results with structural changes in the samples. ****