阻抗张量分解技术在桂北地区AMT数据处理中的应用  

The application of impedance tensors decomposition to AMT data processing in Northern Guangxi area

作　　者：孔志召[1,2] 赵璐[1] 艾虎[1] 魏滨[1] 王泽霞[1] 

机构地区：[1]核工业航测遥感中心,河北石家庄050002 [2]吉林大学地球科学学院,吉林长春130000

出　　处：《物探与化探》2014年第5期1045-1050,共6页Geophysical and Geochemical Exploration

基　　金：中国核工业地质局物探测量专项(201228)

摘　　要：针对AMT测量中由于地表局部不均匀体影响引起的电场畸变效应,以及测线方向与构造走向不垂直等问题引起的一些反演偏差,以桂北地区为例,通过选择合适的方法开展阻抗张量分解,找到最佳的主轴方位,利用有限的资料,提取一维、二维偏离度等信息,并对电性结构的维性特征进行分析,最后使用最佳主轴方位角进行反演,从而得到了符合实际地质情况的反演电阻率断面。与钻孔资料进行对比,结果表明:该方法能够较好地分析地电结构的维性特征,有利于识别隐伏构造。Some inversion errors may be caused either by the distortion effect of the localized conductivity heterogeneity or by the fact that line direction is not perpendicular to the structural strike in the AMT measurement. This study took Northern Guangxi area as the study area： The best orientation of principal axis was found by choosing suitable method to carry out the impedance tensor decomposi- tion. The limited data were used to extract such information as one-dimensional and two-dimensional skew, and the dimensional charac- teristics of electrical structure were analyzed. Finally, the best orientation of principal axis was applied to the 2-D inversion, thus the resistivity inversion section that conforms to the actual geological conditions can be obtained. Drilling verification has demonstrated the effectiveness of this method, which can analyze the dimension characteristics of geo-electric structure better and identify hidden structures.

关 键 词：桂北地区 阻抗张量分解 主轴方向 AMT 视电阻率 

分 类 号：P631[天文地球—地质矿产勘探]