深大长隧道的电磁测深法应用研究

【作者】 王烨；

【导师】 汤井田；

【作者基本信息】 中南大学 ， 地球探测与信息技术， 2005， 硕士

【摘要】 深大长隧道的地球物理宏观预测是当今工程界亟待解决的重大前沿课题。本文紧紧结合当前我国中西部铁路工程建设发展过程中,深大长隧道工程日益增多的实际情况,结合宜(昌)-万(州)铁路工程勘察,针对电磁测深法在深大长铁路隧道勘察中的应用这一课题展开研究。首先简要地叙述了当前深大长隧道工程勘察研究的概况及研究前沿,然后结合大地电磁测深理论提出了高频人文大地电磁测深法。随后根据野外实测数据对该方法的频谱特征进行归纳总结,分析了高频大地电磁测深法和可控源音频大地电磁测深法的噪声来源和干扰特征,并结合实际工程应用对这两种具有代表性的电磁测深方法的技术路线进行了对比研究,详细地论述了由地表不均匀体和地形因素所引起的静态效应产生的影响及校正方法,同时也讨论了两种电磁测深方法的分辨率问题、探测深度问题。接下来,先对高频大地电磁测深法的TE和TM模式下应用结果进行了理论分析和实例比较,又对可控源音频大地电磁测深法的近场效应、过渡带效应和阴影效应进行研究。论文的第五部分着重结合宜(昌)-万(州)铁路工程勘察实例分别论述了高频人文大地电磁测深法和可控源音频大地电磁法在深大长隧道中溶洞探测、断层的定位的应用效果,对两种方法的应用条件、数据处理方法、物探解释理论进行了深入的研究,对于今后开展此类工程勘察设计有较好的指导作用。论文还对高频人文大地电磁法的场源激发类型进行了先期的探讨,得出了一些有用的结论。在论文的最后,对本论文所取得的一些成果进行了简单的总结,并对下一步研究工作的开展提出了建议。更多还原

【Abstract】 It is an important forward topic that the geophysical macroscopic estimation of the deep, big, long tunnel, as well as it has much challage to be ugrently resolved. This paper launches the research that tightly combining the rapid development of the railway engineering and the highly increasing of the number of the deep big long tunnel engineering. At the same time, the paper aims at the applied effects of the Magnetotellurics sounding in this kind of tunnel. Firstly, the paper describes in brief the evolvement and studying foreland in the deep big long tunnel in developed countries, then put forward the high-frequency Cultural Magnetotellurics sounding method (CMT) based on the Magnetotellurics sounding theories. The paper summarizes the CMT frequency spectrum characteristic combining the field observed data, and analyzes the noise source and interference characteristic of the CMT and the CSAMT (Controlled Source Audio-frequency Magnetotellurics). Then, combining the actual engineering application, the paper carries on contrast research about the technique routes of the two representative MT method , discussing in detail the static effects and it’s correction, the static effects result from the earth’s surface inhomogeneous medium and the topographic inequality. The resolution problems and the prospecting depth problems of CMT and CSAMT discussed too. Secondly, after analyzing and contrasting the applied effects in TE model and TM modelof the CMT method, the paper studies the near field effect, transitional belt effect and shadow effect of the CSAMT and method. In the fifth chapter, the paper studies the cavern detection and fault orientation by CMT and CSAMT methods, combining the railway engineering survey of Yichang - Wanzhou railway. The paper carries on thorough research on the applied conditions, data processing, theories of geophysical explanation of CMT and CSAMT. It is a good indicator for this kind of engineering design aftertime. At last, the paper studies originally to the source of the useful conclusions, in the last of the paper, the author summarizes in brief the results of the paper and put forward some suggestions for the future work.更多还原