利用单点六分量地震提取面波频散谱的数值验证  

Numerical verification of extracting surface wave dispersion spectrum from a single point six-componentseismic observation

作　　者：陈锋 王赟[1] 李维 郭高源 秦林鹏 孙丽霞 韦永祥[2] 张宝剑[2] CHEN Feng;WANG Yun;LI Wei;GUO GaoYuan;QIN LinPeng;SUN LiXia;WEI YongXiang;ZHANG BaoJian(School of Geophysics and Information Technology,China University of Geosciences,Beijing 100083,China;Fujian Earthquake Agency,Fuzhou 350001,China)

机构地区：[1]中国地质大学(北京)地球物理与信息技术学院,北京100083 [2]福建省地震局,福州350001

出　　处：《地球物理学报》2023年第10期4269-4278,共10页Chinese Journal of Geophysics

基　　金：国家自然科学基金项目(U1839208,62127815,42150201)联合资助。

摘　　要：面波频散反演是揭示地下速度结构的一项重要手段.传统面波勘探技术侧重于多台站阵列数据频散分析.旋转地震学理论框架下六分量地震观测时,仅利用单台站记录的平动与旋转分量就可以获得面波频散曲线.本文从频率域谐振分析出发,利用模态叠加正演方法,讨论了不同模型下平动与旋转联合估算Rayleigh波相速度的可靠性.结果表明:单台站多分量地震数据估算的频散曲线受多种因素影响,估计过程存在一定的系统误差;典型浅层地质模型下,单点估算与多道面波分析方法(MASW)提取的Rayleigh波频散曲线在低频段吻合性好;若要降低单点多分量地震估算的系统误差,仍需研发配套的波场分离与不同阶频散谱的高精度提取技术.Surface wave dispersion curve inversion is utilized to obtain subsurface velocity structure,but the traditional surface wave exploration technology focuses on the dispersion analysis using multi-station array data.According to rotational seismology,the dispersion curves of surface waves can be recovered by using the translational and rotational measurements recorded by a single station.Based on frequency domain resonance analysis and modal summation numerical tests,we discussed the reliability of the recovered dispersion characteristics of Rayleigh waves in different models.The results verify that the dispersion curve of multi-component seismic data estimated by single station is affected by multiple factors and there are some systematic errors in the estimation procedure.In the case of typical shallow geological model,the dispersion curves of Rayleigh wave estimated by single station and the Multichannel Analysis of Surface Waves(MASW)method have a good agreement in the low frequency band.In order to reduce the systematic error of dispersion curve estimation from single-point multi-component earthquake measurements,we suggest developing the supporting high-precision extraction technology of wave field separation and different order dispersion spectrum.

关 键 词：面波 频散曲线 平动 旋转数值模拟 旋转地震学 

分 类 号：P631[天文地球—地质矿产勘探]