S1P/S2P波分离及SVP横波分裂校正  

S1P/S2P wave separation and shear wave splitting correction for SVP data

作　　者：岳媛媛 钱忠平 聂红梅 孙鹏远 邓志文 李建峰 YUE Yuanyuan;QIAN Zhongping;NIE Hongmei;SUN Pengyuan;DENG Zhiwen;LI Jianfeng(BGP Inc.,CNPC,Zhuozhou,Hebei 072751,China)

机构地区：[1]中国石油东方地球物理公司,河北涿州072751

出　　处：《石油地球物理勘探》2023年第6期1374-1381,共8页Oil Geophysical Prospecting

基　　金：中国石油天然气集团公司科学研究与技术开发项目“三维弹性波数据处理新方法探索研究”(2021DJ3506);东方地球物理公司科研项目“青海横波源3D9C数据处理解释研究与应用”(06-02-2022)联合资助。

摘　　要：对于横波源地震勘探,从资料中提取裂缝信息并进行快、慢横波分离和横波分裂校正,对于方位各向异性横波地震数据成像具有十分重要的意义。横波源勘探数据中的SP转换波(横波转换的纵波)与纵波源勘探数据中的PS转换波(纵波转换的横波),二者之间的差异只是横波分裂发生在下行波或上行波传播过程中。因此,SP波横波分裂特征与PS波类似。本文将PS波的切向能量最小化方法应用到SP横波分裂分析,以求取地下裂缝方向。在三维九分量(3D9C)实际数据应用时,形成了在横波源SP波地震数据CCP(共转换点)道集抽取及动校正等预处理的基础上进行分方位叠加并求取CCP对应的裂缝方向,再进行快、慢转换纵(S1P、S2P)波分离的技术流程。同时,还提出了在快、慢波叠加剖面上拾取层位获取时差的策略,应用该时差进行横波分裂校正后,得到去除了横波分裂效应的转换纵(SVP)波,剖面成像质量得到了进一步的改善。合成数据及实际数据应用结果均表明,S1P和S2P波成像剖面较分离前有明显改善,横波分裂校正后SVP反射能量得到进一步增强,验证了本文方法在实际SP波地震数据进行快、慢波分离和横波分裂校正的可行性。For shear(S)-wave source seismic exploration,extracting fracture information from the data and per-forming fast/slow S-wave separation and S-wave splitting correction are of great significance for S-wave seismic data imaging with azimuthal anisotropy.The difference between SP converted wave(P-wave converted from Swave)in S-wave source exploration data and PS converted wave(S-wave converted from P-wave)is that the Swave splitting occurs in the process of downgoing wave or upgoing wave propagation.Therefore,the S-wave splitting characteristics of the SP wave are similar to those of the PS wave.In this paper,the tangent energy minimization method of PS wave is applied to the S-wave splitting analysis of SP wave to find the direction of underground cracks.In the application of 3D nine-component(3D9C)actual data,a technical process is formed based on the pre-processing of SP wave seismic data including common conversion point(CCP)gather extraction and NMO correction,and the corresponding crack direction of CCP is obtained by azimuthal superposition.In addition,the fast and slow converted(S1P and S2P)wave separation is carried out.At the same time,a strategy is proposed to obtain the time difference by picking up the horizon on the fast and slow wave superimposed profile.After the time difference is applied to the S-wave splitting correction,SVP without the S-wave splitting effect is obtained,and the image quality of the profile is improved.The application results of synthetic data and actual data show that the imaging profiles of S1P and S2P waves are significantly improved compared with those before separation,and the SVP reflection energy is improved after S-wave splitting correction,which verifies the feasibility of the proposed method for fast and slow wave separation and S-wave splitting correction in actual SP wave seismic data.

关 键 词：横波分裂 快慢波分离 横波震源 快横波转换纵(S1P)波 慢横波转换纵(S2P)波 SV波转换纵(SVP)波 

分 类 号：P631[天文地球—地质矿产勘探]