Collaborative Research: Electromagnetic Induction in Geological Formations: A Careful Evaluation of the Subdiffusion Perspective

团队1提案编号： 09-43598主要研究者： 韦斯，切斯特; 540 - 231 - 3651; cj韦斯@vt. edu机构： Virginia TechTeam 2提案编号： 09-43589主要研究者： 埃弗雷特，马克; 979 - 862 - 2129; everett@geo. tamu. edu 德克萨斯州A MTTitle：地质构造中的电磁感应：& 虽然受控源电磁地球物理学经常被誉为地下水文学的潜在突破性技术，但目前的现实是，水文地质学家在解释电磁数据时经常遇到严重的困难。在简单的情况下，地下的电性质是合理的近似由一个平滑或分段恒定的分布，低频电磁感应的经典地球物理方法是有用的，在约束我们的水文系统的知识。 然而，在设置更复杂的情况下？例如，地下的特征是长度尺度依赖的不均匀性？电磁感应的经典方法必须相应地修改。 一个有前途的分析方法使用分数阶微积分的历史方法，以适应规模依赖的岩性复杂性的控制麦克斯韦方程。 通过对分数麦克斯韦响应（FMR）和相应的经典电磁模拟的系统研究，我们的目标是阐明FMR存在的地质环境，并根据水文参数（如孔隙度、粘土含量、孔隙水盐度、裂缝密度、盐楔或污染区的位置）解释FMR，我们目前建议的技术创新是基于将传统的电磁地球物理学扩展到新的领域，随着电磁场向尺度依赖的地质介质中的异常扩散的发展。 然而，电磁地球物理学的广泛影响，无论是传统的还是创新的，都必须更好地传达给水文界。因此，我们计划利用新开发的虚拟学院？OpenEM.org?作为一个平台，以更好地参与水文界在电磁地球物理学的应用。

Team 1Proposal Number: 09-43598Principal Investigator: Weiss, Chester; 540-231-3651; cjweiss@vt.eduInstitution: Virginia TechTeam 2Proposal Number: 09-43589Principal Investigator: Everett, Mark; 979-862-2129; everett@geo.tamu.eduInstitution: Texas A&MTitle: Electromagnetic Induction in Geological Formations: A Careful Evaluation of the Subdiffusion Perspective ABSTRACTWhile controlled-source electromagnetic geophysics has been often hailed as a potential breakthrough technology for subsurface hydrology, the current reality is that hydrogeologists often experience severe difficulties in interpreting electromagnetic data. In simple cases, where the electrical properties of the subsurface are reasonably approximated by a smooth or piecewise-constant distribution, classical geophysical methods of low-frequency electromagnetic induction are useful in constraining our knowledge of the hydrologic system. However, in cases where the setting is more complicated ? for instance, where the subsurface is characterized by length-scale-dependent heterogeneity ? the classical methods of electromagnetic induction must be modified accordingly. A promising analytic approach uses the historical methods of fractional calculus to accommodate scale-dependent lithologic complexity in the governing Maxwell Equations. Through a systematic study of the fractional Maxwell response (FMR) and corresponding classical electromagnetic simulations of appropriate complexity, we aim to illuminate geological settings where the FMR is present and to interpret the FMR in terms of hydrologic parameters such as porosity, clay content, pore water salinity, fracture density, position of a saline wedge or contaminant zone, etc. The technical innovation of our current proposal is based on extending traditional electromagnetic geophysics into new territory with the development of anomalous diffusion of electromagnetic fields into scale-dependent geological media. The broad sweep of electromagnetic geophysics, both traditional and innovative, must however be better communicated to the hydrological community. Accordingly we plan to utilize the newly developed virtual institute ?OpenEM.org? as a platform to better engage the hydrologic community in the application of electromagnetic geophysics.