弹性波逆时偏移的角度域共成像点道集提取方法  

Angle-domain common-image gather extraction based on elastic reverse time migration

作　　者：徐蔚亚 朱成宏[1,2,3] 魏哲枫 张晓语[4] 杜启振 XU Weiya;ZHU Chenghong;WEI Zhefeng;ZHANG Xiaoyu;DU Qizhen(State Key Laboratory of Shale Oil and Gas En-richment Mechanisms and Effective Development,Beijing 100083,China;SINOPEC Key Laboratory of Seismic Elastic Wave Technology,Beijing 100083,China;SINOPEC Petroleum Exploration and Produc-tion Research Institute,Beijing 100083,China;Institute of Oceanographic Instrumentation,Qi-lu University of Technology(Shandong Academy of Sciences),Qingdao,Shandong 266100,China;Key Laboratory of Deep Oil and Gas,China University of Petroleum(East China),Qingdao,Shandong 266580,China)

机构地区：[1]页岩油气富集机理与有效开发国家重点实验室,北京100083 [2]中国石化弹性波理论与探测技术重点实验室,北京100083 [3]中国石化石油勘探开发研究院,北京100083 [4]齐鲁工业大学(山东省科学院)山东省科学院海洋仪器仪表研究院,山东青岛266061 [5]中国石油大学(华东)深层油气重点实验室,山东青岛266580

出　　处：《石油地球物理勘探》2022年第4期870-878,I0006,共10页Oil Geophysical Prospecting

基　　金：国家重点研发计划项目“高分辨率地震成像软件系统开发及应用”(2018YFA0702505);国家自然科学基金—中国石化石油化工联合基金项目“海相深层复杂构造成像与多类型储层预测方法”(U19B6003-004)联合资助。

摘　　要：对于多分量地震勘探,由于介质中纵、横波的耦合作用,多波角道集存在能量串扰和低波数噪声干扰等问题。针对横波Poynting矢量构建过程中存在的应力串扰问题,基于解耦延拓方程及伪横波应力构建方法,对质点振动速度和应力进行解耦,实现了无能量串扰的纵波和横波Poynting矢量构建;在基于Poynting矢量提取PP波反射角和PS波反射角的基础上,提出了基于弹性逆时偏移的PP波和PS波角道集提取方法;针对PP波角度域共成像点道集存在的低波数噪声干扰问题,提出了角度域共成像点道集的角度衰减叠加策略,提高了偏移成像精度。应用模型数据验证了方法的正确性。Due to the coupling effect of P-and S-waves in the medium,multi-wave angle-domain common-image gathers(ADCIGs)encounter the problems such as energy crosstalk and low wavenumber noise in multicomponent seismic exploration.To solve the stress crosstalk problem in the construction of the Poynting vector of S-waves,this study uses the decoupled wave equation and pseudo-Swave stress construction method to decouple the particle vibration velocity and stress,and the Poynting vectors of the P-and S-waves are constructed without energy crosstalk.Then,the PPwave and PS-wave reflected angles are extracted given the Poynting vectors.On this basis,this paper proposes the PP-wave and PS-wave ADCIG extraction method based on the elastic reverse time migration(ERTM).Considering the low wavenumber noise in PP-wave ADCIGs,an angle attenuation superposition strategy for ADCIGs is proposed to improve the migration imaging accuracy.The model test verifies the correctness of the method.

关 键 词：解耦延拓方程 伪横波应力 Poynting矢量 角度域共成像点道集 

分 类 号：P631[天文地球—地质矿产勘探]