基于小波变换的微动勘探频散去噪分析研究  

Research on Denoising Analysis of Microtremor Exploration Dispersion Based on Wavelet Transform

作　　者：徐敏[1] 张宗楼 毕爽爽 鲍现奎 朱丹华[1] Xu Min;Zhang Zonglou;Bi Shuangshuang;Bao Xiankui;Zhu Danhua(Hangzhou Geotechnical Engineering&Surveying Research Institute Co.,Ltd.,Hangzhou Zhejiang 310012,China)

机构地区：[1]杭州市勘测设计研究院有限公司,浙江杭州310012

出　　处：《工程地球物理学报》2025年第2期277-284,共8页Chinese Journal of Engineering Geophysics

基　　金：杭州市城市建设投资集团有限公司重点科技研究项目(编号:HK2024RD48);浙江省建设科研项目(编号:2022K169)。

摘　　要：随着地球物理勘探技术的进步,被动源面波已成为获取地下介质横波速度参数的重要工具。然而,城市环境中的被动源面波数据常常受到噪声干扰,这对空间自相关法的应用提出了挑战。为了解决这一问题,本研究引入了小波变换去噪技术,通过多尺度分解与阈值处理,有效去除了自相关系数中的噪声成分。在数值模拟部分,对理论空间自相关系数即贝塞尔函数进行了加噪处理,并评估了10种不同类型的小波基在降噪分析中的表现。模拟结果显示,cofi5小波基在贝塞尔函数的噪声压制方面表现优异。针对杭州市城南路采集的实测数据,降噪处理后,面波频散能量在2~16 Hz频带范围内的收敛度得到了显著提升。实验结果表明,小波变换去噪技术显著提高了被动源面波空间自相关法的有效频谱范围和准确性,为被动源探测技术的发展提供了强有力的支持。With the advancement of geophysical exploration technology,passive source surface waves have become an important tool for obtaining the shear wave velocity parameters of subsurface media.However,passive source surface wave data in urban environments are often disturbed by noise,posing challenges for the application of spatial autocorrelation method.To address this issue,this study introduces wavelet transform denoising techniques,effectively removing noise components from the autocorrelation coefficient through multiscale decomposition and thresholding.In the numerical simulation section,noise is added to the theoretical spatial autocorrelation coefficient,specifically Bessel function,and the performance of 10 different wavelet bases in denoising analysis is evaluated.The simulation results indicate that the cofi5 wavelet basis performs excellently in noise suppression of Bessel function.For the field data collected from South Road in Hangzhou,denoising treatments significantly improve the convergence of surface wave dispersion energy within the frequency band of 2 to 16 Hz.The experimental results demonstrate that wavelet transform denoising techniques significantly enhance the effective frequency spectrum range and accuracy of the spatial autocorrelation method for passive source surface waves,providing strong support for the development of passive source detection technology.

关 键 词：被动源面波 空间自相关法 小波变换 去噪 

分 类 号：P631.4[天文地球—地质矿产勘探]