3D finite-difference modeling algorithm and anomaly features of ZTEM  

ZTEM三维有限差分数值模拟算法及响应特征研究（英文）

作　　者：Wang Tao Tan Han-Dong. Li Zhi-Qiang Wang Kun-Peng Hu Zhi-Ming Zhang Xing-Dong 王涛;谭捍东;李志强;王堃鹏;胡志明;张兴东(中国地质大学(北京)地下信息探测技术与仪器教育部重点实验室和地球物理与信息技术学院,北京100083)

机构地区：Key Laboratory of Geo-detection Ministry of Education and School of Geophysics and Information Technology, China University of Geosciences, Beijing 100083, China.

出　　处：《Applied Geophysics》2016年第3期553-560,582,共9页应用地球物理（英文版）

基　　金：supported by the Natural Science Foundation of China(No.41374078);Geological Survey Projects of Ministry of Land and Resources of China(No.12120113086100 and 12120113101300)

摘　　要：The Z-Axis tiPPer eiectromagnetic （ZTEM） technique is based on a frequency-domain airbome electromagnetic system that measures the natural magnetic field. A survey area was divided into several blocks by using the Maxwell＇s equations, and the magnetic components at the center of each edge of the grid cell are evaluated by applying the staggered-grid finite-difference method. The tipper and its divergence are derived to complete the 3D ZTEM forward modeling algorithm. A synthetic model is then used to compare the responses with those of 2D finite-element forward modeling to verify the accuracy of the algorithm. ZTEM offers high horizontal resolution to both simple and complex distributions of conductivity. This work is the theoretical foundation for the interpretation of ZTEM data and the study of 3D ZTEM inversion.Z轴倾子电磁法(ZTEM)是一种天然源频率域航空电磁法。本文介绍了ZTEM的野外施工方式,给出了三维情况下倾子矢量以及倾子散度的表达式;由麦克斯韦方程组出发,将研究区域离散成若干长方体单元,采用交错网格有限差分法求得了网格棱边中点处的磁场值,最终整理出倾子矢量和倾子散度,完成三维正演模拟;建立与相关文献中相同的地电模型,对比二维有限元和本文的计算结果,验证了本文正演算法的可靠性,最后通过理论模型算例总结了典型地电模型的响应特征,证明ZTEM无论对于简单还是较为复杂的地电分布,都具有较好的横向分辨率和应用价值,为研究ZTEM方法及ZTEM资料三维反演奠定了基础。

关 键 词：Z-Axis tipper electromagnetic finite-difference method TIPPER three-dimensional forward modeling airbome electromagnetic 

分 类 号：P631.325[天文地球—地质矿产勘探]