摘要
由水平磁偶极子源层状地电模型表面的磁场水平分量H_(x)频率域响应解析公式,运用均匀半空间等效原理,导出了其全区视电阻率的迭代法计算公式,并基于平移算法的快速计算加以验证,提出用平移算法计算初值加速迭代法的计算策略,通过正演计算模型验证了方法的有效性。依此计算了不同地电模型的H_(x)分量全区视电阻率,对比研究了H_(x)分量全区视电阻率对不同地电模型的响应能力。从计算结果可以看出,水平磁偶极子源激发,采用垂直共面装置观测同方向水平磁场H_(x)计算的全区视电阻率,对地电模型层参数变化(厚度和电阻率)均有较好的分辨力。迭代法或平移算法计算的H_(x)全区视电阻率,均能较好刻画出模型地电阻率变化特征,迭代法全区视电阻率尾支曲线较平移算法更能趋近于深部电阻率真值。对于浅部工程地质问题用高频激发,较小收发距接收,可有效分辨缺陷特征。
Based on the frequency domain response formula of the horizontal magnetic field component H_(x) on the surface of the layered geoelectric model of the horizontal magnetic dipole source and using the principle of uniform half-space equivalence,the iterative calculation formula of the whole zone apparent resistivity of the horizontal magnetic field component H_(x) frequency sounding is derived,which is verified by the fast calculation based on the translation algorithm.and the calculation strategy of using the result calculated by the translation algorithm as the initial value to accelerate the iterative method is proposed and proved,the forward calculation modelforward calculation model verifies the effectiveness of the method.Based on this,the whole zone apparent resistivity of H_(x) component of different geoelectric models is calculated,and the response-ability of the whole zone apparent resistivity of the H_(x) component to different geoelectric models is compared and studied.It can be seen from the calculation results that the whole zone apparent resistivity calculated by using the vertical coplanar device to observe the horizontal magnetic field H_(x) in the same direction excited by the horizontal magnetic dipole source has good resolution to the changes of layer parameters(thickness and resistivity)of the geoelectric model.The apparent resistivity of H_(x) calculated by iterative method or translation algorithm can better describe the variation characteristics of model earth resistivity.The tail branch curve of whole zone apparent resistivity by iterative method is closer to the true value of deep resistivity than by translation algorithm.For shallow engineering geological problems,defect characteristics can be effectively distinguished by high-frequency excitation and small receiving and transmitting distance.
作者
徐维
罗维斌
张克聪
赵才生
XU Wei;LUO Weibin;ZHANG Kecong;ZHAO Caisheng(The 149 Team of Gansu Coalfields Geological Bureau,Lanzhou 730000,China;Lanzhou Resources and Environment Vocational and Technical University,Lanzhou 730000,China;Gansu Jingyuan Coal Industry And Electricity Power CO..LTD,Baiyin 730900,China)
出处
《物探化探计算技术》
CAS
2023年第2期242-251,共10页
Computing Techniques For Geophysical and Geochemical Exploration
基金
甘肃省教育厅产业支撑计划项目(2021CYZC-67)。
关键词
水平磁偶极子源
全区视电阻率
迭代法
平移算法
一维层状模型
horizontal magnetic dipole source
apparent resistivity of the whole zone
iterative method
translation algorithm
one dimensional layered model
