Acquisition of Electrical Impedance Analyzer for the ASU Geological Sciences Mineral and Rock Physics Laboratory

这笔拨款为亚利桑那州立大学（ASU）矿物和岩石物理实验室购买电化学阻抗分析系统的费用提供部分支持。PI是亚利桑那州立大学的地质学教授，他将利用这台设备研究地球材料的电学特性。大地电磁测深和地磁测深揭示了各种地壳和地幔环境中的异常高电导率带。为了正确地反演和解释大地电磁响应函数，必须在实验室中确定地球材料在合适频率范围内的电响应。购买的设备将包括阻抗分析系统，包括频率响应分析仪、电位器、个人计算机和数据采集/控制和数据分析/建模的专门软件。该设备将与高温气体混合炉，多砧高压装置，以及其他类型的炉和压力容器接口。利用该设备进行的研究包括：1)低熔体分数下熔体成分和结构对部分熔融体系整体电学性质的影响；2)压力和温度组合对无水矿物和地壳、地幔岩石电学性质的影响；3)含水和名义上无水矿物中氢对电学性质的影响。这些结果将用与离子过程模型相关的等效电路来解释。这些研究的结果将对大地电磁资料的解释和建模具有重要意义，并将对各种地质环境下的物理传输过程提供新的认识。最终的好处将是更详细地了解地球内部深处物质的温度分布和物理状态

0092412 Tyburczy This grant provides partial support for the costs of acquiring an electrochemical impedance analysis system for the Mineral and Rock Physics Laboratory at Arizona State University (ASU). The PI is Professor of Geology at Arizona State University and will utilize this equipment for studies of the electrical properties of earth materials. Magnetotellurics and geomagnetic depth sounding have revealed zones of anomalously high electrical conductivity in a variety of crustal and mantle environments. In order to properly invert and interpret magnetotelluric response functions, the electrical response of Earth materials over a suitable frequency range must be determined in the laboratory. The equipment purchased will consist of an impedance analysis system consisting of a frequency response analyzer (FRA), a potentiostat, a personal computer and specialized software for data acquisition/control and data analysis/modeling. The equipment will be interfaced with a high temperature gas mixing furnace, with a multiple anvil high pressure device, and with other types of furnaces and pressure vessels. Studies to be pursued with this equipment include 1) the influence of melt composition and texture at low melt fraction on the bulk electrical properties of partially molten systems 2) effects of combined pressure and temperature on electrical properties of anhydrous minerals and rocks of the crust and mantle, and 3) the influence of hydrogen in hydrous and nominally anhydrous minerals on electrical properties. The results will be interpreted in terms of equivalent electrical circuits that can be related to models of ionic processes. The results of these studies will be important for the interpretation and modeling of magnetotelluric data and will also shed new light on physical transport processes in a variety of geological environments. The ultimate benefits will be more detailed understanding of the temperature profile and physical state of matter at depth in the Earth's interior.***