大地电磁测深数据互参考处理的应用研究  

A STUDY ON THE APPLICATION OF MUTUAL REFERENCE TECHNIQUE IN MAGNETOTELLURIC SOUNDING DATA

作　　者：戴前伟[1,2] 陈勇雄[1] 侯智超[1] 

机构地区：[1]中南大学地球科学与信息物理学院,湖南长沙410083 [2]广州建设工程质量安全检测中心有限公司,广东广州510440

出　　处：《物探化探计算技术》2013年第2期147-154,118,共8页Computing Techniques For Geophysical and Geochemical Exploration

基　　金：中南大学硕士生学位论文创新项目(2011ssxt055);湖南省研究生科研创新项目(CS2010B052)

摘　　要：大地电磁测深勘探方法易受电台、电网、工业游离电流等人为因素干扰,致使资料数据离差大、曲线形态畸变、可信度差。根据噪声对大地电磁测深张量阻抗估算值的影响规律和大地电磁测深远参考技术的应用效果,阐述了远参考技术的一种折中方案,即互参考道方法。选取不同参考距离、不同质量的大地电磁实测数据作为互参考点,通过计算经互参考处理后的大地电磁测深数据得出相干度、信噪比以及卡尼亚电阻率～相位曲线,分析了经互参考道处理后MT资料的效果。结果表明,该方法是有效的,并总结了应用此方法的一些问题。Magnetotelluric sounding exploration vulnerable to the interference of radio stations,power grids,industrial free current and other human factors,resulting data features large deviation,distorted curve shape and low reliability.In this paper,based on the estimation formula of magnetotelluric impedance tensor,the degree of deviation of impedance tensor due to cultural noises is discussed.When there are uncorrelated noises in the electromagnetic components,a higher precise estimation of impedance tensor is obtained.As we known,the magnetic component of MT will not change too much in a certain distance,and if this distance is longer enough,the cultural noise at one site will not related to the other.This is the reason why we use the magnetic mutual reference method to improve the quality of field data.In this paper,a compromise scenario of the remote reference technique,the so-called mutual reference technique is expounded.The effect of application of this method is analyzed.The results show that this method is effective,and some problems in application are summarized.

关 键 词：大地电磁测深 互参考技术 标准偏差 相干度 信噪比 

分 类 号：P631.325[天文地球—地质矿产勘探]