大地电磁多站远参考在压制城市游散电流近场干扰中的应用  

Application of magnetotelluric multi-station remote reference in suppressing near field interference of urban stray current

作　　者：邰书坤 李桐林[1] 朱威[2] 王大勇[2] 王刚[2] TAI Shu-kun;LI Tong-lin;ZHU Wei;WANG Da-yong;WANG Gang(College of Geo-exploration Science and Technology,Jilin University,Changchun 130026,China;Institute of Geophysical and Geochemical Exploration,Chinese Academy of Geological Sciences,Langfang 065000,Hebei,China)

机构地区：[1]吉林大学地球探测科学与技术学院,长春130026 [2]中国地质科学院地球物理地球化学勘查研究所,河北廊坊065000

出　　处：《世界地质》2021年第3期644-654,共11页World Geology

基　　金：国家科技重大专项大型油气田及煤层气开发子课题《南海重磁震地学断面综合研究》(2016ZX05026007-001);中国地质调查局项目(DD20190556);中国博士后科学基金特别资助(站前)项目(2020TQ0114)资助。

摘　　要：通过在北京南中轴强干扰区不同距离处布设6个大地电磁测深试验点,分析受干扰的大地电磁测深数据,总结了城市游散电流对大地电磁测深数据干扰特征,根据干扰特征选择远参考法进行去噪。首先利用同步布设的11个不同距离远参考站分别对测点进行远参考处理,分析单站远参考的局限性,然后提出不同频段最优化组合的多站远参考处理方式。在>0.04400 Hz、0.04400~0.00550 Hz和0.00550~0.00057 Hz频段分别选取距测点80 km、220 km和360 km处远参考站处理结果,最优化组合得到全频段大地电磁测深曲线。研究表明,城市游散电流对大地电磁测深的主要干扰方式为近场干扰,27 km以外测点数据经多站远参考处理后近场干扰可得到有效压制,实现了数据质量提升的目的,优于单站远参考处理方式。By setting six magnetotelluric sounding test points at different distances in the strong interference area of Beijing south-central axis,the disturbed magnetotelluric sounding data are analyzed and the interference characteristics of urban stray current on magnetotelluric sounding data are summarized.Based on the interference characteristics,the remote reference method is selected for de-noising.Firstly,11 remote reference stations with different distances are used to process the remote reference of the measuring points,and the limitation of the single station remote reference is analyzed.Then,the multi-station remote reference processing method with the optimal combination of different frequency bands is proposed.The full frequency band magnetotelluric sounding curves are obtained by the optimal combination,which selected the processing results of remote reference stations at 80 km,220 km and 360 km away from the measuring points in the frequency bands>0.04400 Hz,0.04400~0.00550 Hz and 0.00550~0.00057 Hz,respectively.The research results show that the main interference mode of urban stray current to magnetotelluric sounding is near-field interference.The near field interference can be effectively suppressed after the multi-station remote reference processing of the data from the measuring point 27 km away,and the purpose of data quality improvement is realized,which is better than the single station remote reference processing.

关 键 词：城市游散电流 大地电磁测深 近场干扰 多站远参考 

分 类 号：P631.3[天文地球—地质矿产勘探]