地震数据时空变转换点道集抽取  

Spatiotemporally varying common conversion point gather extraction for seismic data

作　　者：孙辉 徐若格 张健 岳玉波 李猛 任洪涌 陈瑞 SUN Hui;XU RuoGe;ZHANG Jian;YUE YuBo;LI Meng;REN HongYong;CHEN Rui(Faculty of Geosciences and Environmental Engineering,Southwest Jiaotong University,Chengdu 611756,China;School of Geoscience and Technology,Southwest Petroleum University,Chengdu 610500,China)

机构地区：[1]西南交通大学地球科学与环境工程学院,成都611756 [2]西南石油大学地球科学与技术学院,成都610500

出　　处：《地球物理学进展》2024年第4期1440-1446,共7页Progress in Geophysics

基　　金：国家重点研发计划(2022YFFO802600);国家自然科学基金(42374166,42204108);四川省自然科学基金(2023NSFSC0770,2023NSFSC0768);中央高校基本科研业务费(2682022ZTPY002,2682022ZTPY088)联合资助。

摘　　要：共转换点(CCP)道集提取是转换波地震数据处理的重要步骤,直接影响着速度建模与成像的效果.常规CCP道集选排方法仍然是以整道选排为主,主要为渐近逼近道分类法,即渐进转换点(ACP)道集提取,此类方法能在一定程度上能够满足深部地层的成像要求,但是难以保证浅层的成像效果.针对这一问题,本文提出了时空变转换点道集提取方法,通过计算CCP的空间位置,结合转换波双程时来确定输入转换波数据道同输出的CCP道之间的映射关系,并将反射地震信号映射到准确的时空位置.能够有效处理非对称的转换波传播路径,从而有效提高CCP道集的抽取质量.数值模拟以及实际数据计算结果表明:本文提出的CCP道集提取方法具有较好的实际应用效果.Common Conversion Point (CCP) gather extraction is an important step in converted wave seismic data processing. It is also the main difference between converted wave processing and P-wave processing,and directly affects the results of velocity modeling and imaging. The conventional CCP gather selection and sorting method is still based on the whole trace selection and sorting,mainly the asymptotic approximation trace classification method,that is,the Asymptotic Conversion Point (ACP) gather extraction. This kind of method can satisfy the imaging requirements of deep strata to a certain extent,but it is difficult to guarantee shallow imaging effects. To solve this problem,this paper proposes a spatiotemporally variable conversion point gather extraction method. By calculating the spatial position of the CCP and combining the converted wave two-way traveltime,the mapping relationship between the input converted wave data and the output CCP gather is determined,and reflected seismic signals are mapped to accurate spatiotemporal locations. It can effectively handle asymmetric converted wave propagation paths,thereby effectively improving the extraction quality of CCP gathers. Numerical simulation and field data calculation results show that the CCP gather extraction method proposed in this paper has good practical application effects.

关 键 词：转换波 地震数据处理 共转换点道集 道集提取 渐进转换点道集 

分 类 号：P631[天文地球—地质矿产勘探]