石油物探2025，Vol.64Issue(4)：667-678,12.DOI:10.12431/issn.1000-1441.2024.0015
基于频域Hampel识别的海洋MT数据脉冲噪声压制方法
Impulse noise suppression method for marine MT data based on frequency-domain Hampel identification
摘要
Abstract
The marine magnetotelluric(MT)method utilizes the natural MT signal received by the ocean-bottom electromagnetic(OBEM)stations,and calculates the apparent resistivities and phases based on the impedance tensor estimation to investigating the sub-oceanic conductivity structures.The OBEM often generate noises that appear as irregular high-frequency pulses with particular frequency characteristics.Consequently,the impedance tensors of the affected frequencies deviate from the true values,which makes it difficult to interpret the data correctly.To mitigate the influence of the impulse noise on marine MT signals,an impulse noise suppression method based on frequency-domain Hampel identification is proposed.Firstly,the low-frequency energy of marine MT data is reduced by first-order differential pre-whitening to improve the noise recognition rate of the Hampel identifier.Then,the frequencies affected by the impulse noise in the four components of MT data are identified using the Hampel identifier in the frequency domain.Finally,considering the stability of MT impedance estimation,the noise frequencies in the four components are merged and universally amplitude-attenuated to suppress the impulse noise,so that the apparent resistivity and phase distortion can be corrected.Based on the periodic difference between MT signal and impulse noise,the autocorrelation function which can be used for measured data is introduced to evaluate the efficacy of the proposed method in suppressing impulse noise.Moreover,the proposed method is tested using the synthetic and measured MT data.The results show that the proposed method can effectively suppress the impulse noise in the marine MT data,reduce the periodic peaks caused by the noise in terms of the autocorrelation function curve,correct the apparent resistivity and phase distortion induced by the noise,and thereby enhances the quality of MT data.关键词
海洋大地电磁法/脉冲噪声/Hampel识别器/自相关函数/噪声压制Key words
marine MT/impulse noise/Hampel identifier/autocorrelation function/noise suppression分类
能源科技引用本文复制引用
徐天,罗鸣..基于频域Hampel识别的海洋MT数据脉冲噪声压制方法[J].石油物探,2025,64(4):667-678,12.基金项目
国家自然科学基金项目(42474106,U2241201)、山东省自然科学基金项目(ZR2023MD104)和山东省重点研发计划(2020CXGC010706)共同资助.This research is financially supported by the National Natural Science Foundation of China(Grant Nos.42474106,U2241201),the Natural Science Foundation of Shandong Province(Grant No.ZR2023MD104),and the Key Research and Development Program of Shandong Province(Grant No.2020CXGC010706). （42474106,U2241201）
