摘要
在测量电场和磁场分量的过程中,由于地质因素、工频、人文干扰和其他外界因素以及观测系统所造成的干扰等,常常会使实际数据含有噪声,从而影响到视电阻率和相位的计算以及后续的正反演工作。为提高处理效果,在已有快速算法的基础上,将改进阈值的TI小波去噪法应用在大地电磁信号去噪中。利用该方法对大地电磁信号去噪,可以达到既有效去除噪声又较大程度地维持原始信号形态的目的。在对实测大地电磁数据进行去噪处理后的结果显示,该去噪方法使信号数据的突变现象得到有效的控制和减少,并使时间序列、视电阻率曲线和相位曲线的质量都有了明显的改善,因而具有较好的去噪效果。
In the process of measuring electric field and magnetic field components,due to interference from geological factors,power frequency,human activities,and other external factors as well as the observation system,there often exist many kinds of noises in actual data,which affect the computing of apparent resistivity and phase and the subsequent forward and inversion work.In order to improve the processing effect,the authors applied the TI wavelet denoising method based on improved threshold to the denoising of magnetotelluric signals on the basis of the existing fast algorithm.By using the denoising method,not only the noise can be removed effectively,but also the original shape of signal can be preserved at a large extent.After dealing with the measured magnetotelluric signal data by this method,the authors detected that the denoising method can make the mutation phenomenon under effective control and decrease,and furthermore it improves significantly the quality of time series,apparent resistivity curve and phase curve,thus it has a good denoising effect for magnetotelluric signal.
作者
曹小玲
严良俊
陈清礼
CAO Xiao-Ling;YAN Liang-Jun;CHEN Qing-Li(Key Laboratory of Exploration Technologies for Oil and Gas Resources in Ministry of Education,Yangtze university,Wuhan 430100,China;Hubei Cooperation Innovation Center of Unconventional Oil and Gas,Wuhan 430100,China;School of Information and Mathematics,Yangtze university,Jingzhou 434023,China)
出处
《物探与化探》
CAS
CSCD
北大核心
2018年第3期600-607,共8页
Geophysical and Geochemical Exploration
基金
国家自然科学基金项目(41274082
U1562109)
长江大学长江青年基金项目(2015cqn76)
长江大学重磁电勘探研究中心创新基金项目(7011201803xm)
关键词
小波分析
去噪
平移不变量
大地电磁信号
wavelet analysis
denoising
translation invariance
magnetotelluric signal
