噪声层析成像技术在豫西三门峡地区隐伏断裂探测中的应用  

Application of noise tomography technology in buried faults detection in Sanmenxia area,Western Henan Province

作　　者：侯颉[1,2] 余大新 叶庆东[1] 王磊[1] 乔龙[1] 郭长辉 HOU Jie;YU DaXin;YE QingDong;WANG Lei;QIAO Long;GUO ChangHui(The First Monitoring and Application Center,China Earthquake Administration,Tianjin 300180,China;Institute of Geophysics,China Earthquake Administration,Beijing 100081,China)

机构地区：[1]中国地震局第一监测中心,天津300180 [2]中国地震局地球物理研究所,北京100081

出　　处：《地球物理学进展》2023年第4期1473-1486,共14页Progress in Geophysics

基　　金：三门峡市活断层探测与地震危险性评价项目(HT-2017-01);国家自然科学基金(41504073)联合资助。

摘　　要：三门峡市位于豫陕晋三省交汇处,该地区发育有多条大型隐伏断裂.为进一步揭示三门峡地区隐伏断裂的分布特征及复杂的沉积环境,本文选取2018年10月—2019年8月期间,三门峡地区及邻区内47个固定台站和30个宽频带流动台记录的连续波形资料,采用波形互相关和叠加运算获得台站间格林函数,并用小波变换频时分析技术提取了2307条双台间基阶瑞雷波相速度频散曲线,最后采用噪声层析成像方法获得了研究区4~40 s的瑞雷波相速度分布图像.结果表明,4~10 s周期相速度分布受地表造特征影响较大,沉积盖层、盆地表现为相对低速,结晶基底呈现出相对高速;区内断层多位于高低速异常转换区,对速度异常分布具有一定的控制作用;区内MS4级以上的地震主要发生于黄河以北,且主要分布在高低速度转换区及其邻近区域.Sanmenxia lies at the confluence of Henan,Shaanxi and Shanxi provinces,and there are many large concealed faults in the area.In order to further reveal the spatial distribution of the buried faults and the complex sedimentary environment of this city,the continuous waveform data of vertical components recorded by 30 broadband mobile stations and 47 fixed stations in Sanmenxia area and its adjacent area from October 2018 to August 2019 are selected,the empirical Green's function between stations is obtained through waveform cross-correlation and superposition operation,and 2307 basic order Rayleigh wave phase velocity dispersion curves between two stations are extracted by wavelet transform frequency-time analysis technology.Then,the Rayleigh wave phase velocity distribution images of Sanmenxia and its adjacent area in Henan Province are obtained by noise tomography.The results show that the phase velocity distribution of 4~10 s periodic is closely related to the characteristics of surface structure.The sedimentary layers and basin show relatively low velocity,and the crystalline basement shows relatively high velocity.The faults in the area are mostly located in the high and low velocity anomaly conversion area,which plays a certain role in controlling the distribution of velocity anomalies.Earthquakes above MS 4 in the area mainly occur in the north of the Yellow River and are mainly distributed in the high-low velocity conversion area and its adjacent areas.

关 键 词：三门峡及邻区 地壳浅部结构 噪声层析成像 相速度频散 隐伏断裂 

分 类 号：P315[天文地球—地震学]