基于VMD的随掘地震超前探测信号谱白化方法研究  

Research on Spectral Whitening Method of Seismic While Drilling Ahead Detection Signals Based on VMD

作　　者：计子琦 张学强[1] 张海江 查华胜 梅欢 程婷婷 JI Ziqi;ZHANG Xueqiang;ZHANG Haijiang;ZHA Huasheng;MEI Huan;CHENG Tingting(Institute of Geophysics&Geomatics,China University of Geoscience(Wuhan),Wuhan 430074,China;Anhui Wantai Geophysical Technology Co.Ltd.,Hefei 230000,China)

机构地区：[1]中国地质大学(武汉)地球物理与空间信息学院,武汉430074 [2]安徽万泰地球物理技术有限公司,合肥230000

出　　处：《CT理论与应用研究（中英文）》2021年第2期148-160,共13页Computerized Tomography Theory and Applications

摘　　要：随掘地震超前探测震源具有连续、非可控的特点,需要使用互相关技术将连续震源记录转换为等效脉冲震源记录以获取有效反射信号。但随掘地震超前探测信号往往包含一些能量较强且频带较窄的优势频率成分,使得互相关处理会引入较严重的干扰。为此,本文提出将基于变分模态分解(VMD)的希尔伯特谱白化方法应用于随掘地震超前探测信号。该方法首先利用VMD将地震信号分解为若干个本征模态函数(IMF),再对各IMF应用希尔伯特变换进行时频分解,最后使用白化滤波器对其希尔伯特谱进行谱白化。数值模拟结果表明基于VMD的希尔伯特谱白化方法能够在保持各道信号一致性的同时均衡信号的不同频率成分,有效压制互相关结果中的虚假同相轴,加快主峰旁瓣衰减。将本文方法应用于安徽淮北杨庄煤矿某巷道实际数据,成功探测了掌子面前方存在的断层构造,表明该方法具有较好的实用性。Seismic source of seismic while drilling ahead detection is consistent and uncontrollable,which requires to convert continuity source records into equivalent pulse source records by cross-correlation to obtain effective reflected signals.However,as the signal often contain dominant frequencies with narrow frequency band and relatively large amplitude,so the method of cross-correlation processing will lead to serious interference.This article proposes to apply the Hilbert spectral whitening method which based on VMD(variational mode decomposition)to signals of seismic while drilling ahead detection.Firstly,this method decomposes the seismic signals into multiple IMF(intrinsic mode function)with VMD,then the IMF is decomposed by Hilbert transform,finally,the Hilbert spectrum is whitened by a whitening filter.The numerical simulation results show that the Hilbert spectrum whitening method which based on VMD can not only ensure well consistency of signals for each trace,but also equalize the different frequency components of signals,effectively suppress the false lineups in the cross-correlation records,and accelerate the attenuation of the sidelobe of the main peak.The method proposed in the article is applied to the actual data of a tunnel in Yangzhuang coal mine,Huaibei,Anhui province,and the fault structure in front of the tunnel face is successfully detected,which shows that the method is very practical.

关 键 词：随掘地震超前探测 变分模态分解 希尔伯特谱白化 

分 类 号：O242[理学—计算数学] P631[理学—数学]