VTI介质克希霍夫叠前深度偏移及其应用  

VTI Media Kirchhoff Pre-Stack Depth Migration Technology and Its Application

作　　者：夏常亮[1,2] 王永明 夏密丽 刘红久 胡浩 王祥春 XIA Changliang;WANG Yongming;XIA Mili;LIU Hongjiu;HU Hao;WANG Xiangchun(School of Geophysics and Information Technology,China University of Geosciences,Beijing 100083,China;Changqing Branch,Geophysical Research Institute,BGP,CNPC,Xi＇an,Shaanxi 710021,China)

机构地区：[1]中国地质大学地球物理与信息技术学院,北京100083 [2]中国石油东方地球物理勘探有限责任公司研究院长庆分院,西安710021

出　　处：《新疆石油地质》2018年第6期732-736,共5页Xinjiang Petroleum Geology

摘　　要：针对叠前深度偏移速度反演多解性及层位标定和偏移结果不匹配,以伊拉克某构造复杂区块地震资料为例,详细介绍了垂直对称轴横向各向同性(VTI)介质的克希霍夫(Kirchhoff)叠前深度偏移及其应用和注意事项。提出利用剥层层速度修正方法反演层速度和测井曲线趋势约束联合解决速度反演多解性问题;利用叠前时间偏移均方根速度场通过约束速度反演(CVI)获得初始沿层层速度,从而保证初始层速度场的准确性和有效减少剥层层速度修正方法反演层速度的迭代次数;通过VTI介质的偏移解决偏移结果与层位标定不匹配问题。实际应用表明,前述Kirchhoff叠前深度偏移流程,能够有效提高叠前深度偏移工作效率,获得可靠性更强的深度域层速度模型,有效提高速度反演精度,获得与井上层位一致的地震层位,满足勘探开发的需求。Regarding the multiple solutions of velocity inversion of pre-stack depth migration（PSDM）and the mismatch between horizon calibration and migration results, and taking the seismic data of a district with complex structures in Iraq as a case, the paper detailedly introduces the VTI media （Transversely Isotropy with vertical axis of symmetry） Kirchhoff PSDM technology and its application and notices.The paper proposes a combined method which uses interval velocity inversion with interval-stripping velocity correction method and logging curve trend constrain method to solve the multiplicity problem; obtains the initial interval velocity through constrained velocity inversion（CVI） in a root-mean-square velocity field of pre-stack time migration to ensure the accuracy of the initial interval velocity field and effectively decrease the iteration numbers of interval velocity inversion with interval-stripping velocity correction method; and solves the mismatch between the migration results and horizon calibration by using VTI media migration. The actual application results show that the above mentioned Kirchhoff pre-stack depth migration process and its notices can effectively improve the work efficiency of pre-stack depth migration and obtain more reliable velocity model in depth domain, and can increase the accuracy of velocity inversion to obtain horizons corresponding to drilling stratification.

关 键 词：Kirchhoff叠前深度偏移 横向各向同性介质 THOMSEN参数 层剥离 层速度 

分 类 号：P631.4[天文地球—地质矿产勘探]