海底地震数据积分法叠前时间域成像方法
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摘要
海底地震(OBS)采集包括海底拖缆(OBC)和海底节点(OBN)两种观测方式。采集时激发点位于海面而接收点置于海底,建立在同一基准面假设前提下的传统地震成像方法不再适应OBS数据。本文首先推导了OBS上、下行波不同深度反射点轨迹的计算公式,用图示法直观地展示了各自共接收点道集数据的覆盖范围;然后以镜像成像理论为指导,推导了下行波积分法叠前时间偏移旅行时计算公式,同时推导了相应的上行波旅行时计算公式,并给出了上、下行波成像时间校正和均方根速度的转换公式;最后描述了OBS叠前时间偏移加权函数的计算公式。二维模型和三维实际数据应用结果表明,用下行波代替上行波成像,不仅能够显著改善浅层成像效果,且成像结果的横向范围得到明显的扩展。
The ocean bottom seismic(OBS)acquisition includes two ways of acquisition,i.e.ocean bottom cable(OBC)and ocean bottom node(OBN).Because shot points are located in the sea surface and receivers are placed in the sea bottom,the assumptions of traditional seismic imaging,which is based on the same datum,is no longer adapt to the OBS data.So we propose in the paper the Kirchhoff prestack time migration for ocean bottom seismic data.First the calculation formula of the travel of down-going and up-going waves from reflection points are derived,and graphs show directly the coverage range of their respective common-receiver-point gathers data.Then using the mirror imaging theory as a guidance,the calculation formulas of travel time of down-going and up-going waves for Kirchhoff time migration are given,and conversion methods between imaging time corrections and RMS velocity in the formulas are clearly specified.Finally,the calculation formula of OBS seismic prestack time migration weighted function is described.
The ocean bottom seismic(OBS)acquisition includes two ways of acquisition,i.e.ocean bottom cable(OBC)and ocean bottom node(OBN).Because shot points are located in the sea surface and receivers are placed in the sea bottom,the assumptions of traditional seismic imaging,which is based on the same datum,is no longer adapt to the OBS data.So we propose in the paper the Kirchhoff prestack time migration for ocean bottom seismic data.First the calculation formula of the travel of down-going and up-going waves from reflection points are derived,and graphs show directly the coverage range of their respective common-receiver-point gathers data.Then using the mirror imaging theory as a guidance,the calculation formulas of travel time of down-going and up-going waves for Kirchhoff time migration are given,and conversion methods between imaging time corrections and RMS velocity in the formulas are clearly specified.Finally,the calculation formula of OBS seismic prestack time migration weighted function is described.
引文
[1] 耿建华,董良国,马在田,等.海底节点长期地震观测:油气田开发与CO2地质封存过程监测[J].地球科学进展,2011,26(6):669-677.GENG Jianhua,DONG Liangguo,MA Zaitian,et al.Ocean bottom nodes time-lapse seismic survey for monitoring oil and gas production and CO2 geological storage[J].Advances in Earth Science,2011,26(6):669-677.
[2] Holloway A,Grant D,Watts G,et al.The future of deepwater ocean bottom seismic:Are flying nodes the next big step?[C].SEG Technical Program Expanded Abstracts,2015,34:115-119.
[3] Gestel J,Heureux E,Sandschaper J.Atlantis “Beyond 4D” ocean bottom nodes acquisition design[C].SEG Technical Program Expanded Abstracts,2015,34:125-129.
[4] Sergio G,Russell E.Mirror imaging of OBS data[J].First Break,2007,25(11):37-42.
[5] White J E,Lindsay R B.Seismic waves:Radiation,transmission,and attenuation[J].Physics Today,1967,20(2):74-75.
[6] Godfrey R J,Kristiansen P,Armstrong B,et al.Imaging the Foinaven ghost[C].SEG Technical Program Expanded Abstracts,1998,17:1333-1355.
[7] Ebrom D,Li X,Sukup D.Facilitating technologies for permanently instrumented oil fields[J].The Leading Edge,2000,19(3):282-285.
[8] Ronen S,Comeaux L,and Miao X G.Imaging downgoing waves from ocean bottom stations[C].SEG Technical Program Expanded Abstracts,2005,24:963-967.
[9] Pica A,Manin M,Granger P Y,et al.3D SRME on OBS data using waveform multiple modelling[C].SEG Technical Program Expanded Abstracts,2006,25:2659-2663.
[10] Muijs R,Robertsson J O,Holliger K.Prestack depth migration of primary and surface-related multiple reflections,Part Ⅰ:Imaging[J].Geophysics,2007,72(2):S59-S69.
[11] Barr F J,Sanders J I.Attenuation of water-column reverberations using pressure and velocity detectors in a water-bottom cable[C].SEG Technical Program Expanded Abstracts,1989,8:653-656.
[12] 陈浩林,张保庆,秦学彬,等.海上OBC地震勘探高精度潮汐校正方法[J].石油地球物理勘探,2014,49(增刊1):1-4.CHEN Haolin,ZHANG Baoqing,QIN Xuebin,et al.High resolution tide correction method for seismic OBC prospecting[J].Oil Geophysical Prospecting,2014,49(S1):1-4.
[13] 程元方,李素闪,张文栋,等.海底电缆资料处理关键技术及其应用[J].石油地球物理勘探,2017,52(增刊2):26-31.CHENG Yuanfang,LI Sushan,ZHANG Wendong,et al.Key techniques for OBC data processing[J].Oil Geophysical Prospecting,2017,52(S2):26-31.
[14] 贺兆全,张保庆,刘原英,等.双检理论研究及合成处理[J].石油地球物理勘探,2011,46(4):522-528.HE Zhaoquan,ZHANG Baoqing,LIU Yuanying,et al.Response characteristics of dual-sensor and their application in OBC data processing[J].Oil Geophysical Prospecting,2011,46(4):522-528.
[15] 刘帅,季晓慧,卢俊,等.CPU与GPU协同并行的多分量地震数据各向异性叠前时间偏移[J].石油地球物理勘探,2019,54(1):65-72.LIU Shuai,JI Xiaohui,LU Jun,et al.Multi-component anisotropy prestack time migration based on collaborative parallel computing with CPU and GPU[J].Oil Geophysical Prospecting,2019,54(1):65-72.
[16] 吴丹,龚仁彬,王从镔,等.最小二乘叠前时间偏移在地震数据规则化中的应用[J].石油地球物理勘探,2019,54(1):36-44.WU Dan,GONG Renbin,WANG Congbin,et al.Seismic data regularization via least-squares prestack time migration[J].Oil Geophysical Prospecting,2019,54(1):36-44.
[17] 钟广见,刘大锰,冯常茂,等.OBS纵波资料镜像叠前时间偏移处理[J].热带海洋学报,2014,33(3):46-51.ZHONG Guangjian,LIU Dameng,FENG Changmao,et al.Mirroring pre-stack time migration processing for OBS P-wave data[J].Journal of Tropical Oceano-graphy,2014,33(3):46-51.
[18] Zhang Y,Gray S,Young J.Exact and approximate weights for Kirchhoff migration[C].SEG Technical Program Expanded Abstracts,2000,19:1036-1039.
[19] Dellinger J,Gray S,Murphy G,et al.Efficient two and one-half dimensional true-amplitude migration[C].SEG Technical Program Expanded Abstracts,1999,18:1540-1543.
[20] Schleicher J,Tygel M,Hubral P.3-D true amplitude finite-offset migration[J].Geophysics,1993,58(8):1112-1126.
[21] Bleistein N,Cohen J and Stockwell J.Mathematics of Multidimensional Seismic Inversion[R].Summer School in Mathematical Geophysics,Stanford University,1998.
[22] Beal E,Salo E,Corcoran C.Lessons from the deep processing ocean bottom seismic data[C].SEG Technical Program Expanded Abstracts,2014,33:3679-3684.
[23] Pacal E,Stewart R,Baysal E,et al.Seismic imaging with ocean-bottom nodes(OBN):mirror migration technique[C].SEG Technical Program Expanded Abstracts,2015,34:4039-4043.
[24] Alerini M,Traub B.Prestack depth imaging of ocean-bottom node data[J].Geophysics,2009,74(6):57-63.
[25] Muijs R,Robertsson J O,Holliger K.Prestack depth migration of primary and surface-related multiple reflections,Part Ⅱ:Identification and removal of resi-dual multiples[J].Geophysics,2007,72(2):71-76.
[26] Duan Y,Sava P.Elastic reverse-time migration with OBS multiples[C].SEG Technical Program Expanded Abstracts,2014,33:4071-4074.
[27] Xia G,Clarke R,Etgen J,et al.OBS multiple attenuation with application to the deep water GOM Atlantis OBS nodes data[C].SEG Technical Program Expanded Abstracts,2006,25:2654-2658.
[28] Amundsen L,Ikelle L,Robertsson J,et al.Wavefield decomposition of seabed node marine recordings[C].SEG Technical Program Expanded Abstracts,2013,32:146-150.
[29] Jiang Z,Yu J,Schuster G T,et al.Migration of multiples[J].The Leading Edge,2005,24(3):315-318.
[2] Holloway A,Grant D,Watts G,et al.The future of deepwater ocean bottom seismic:Are flying nodes the next big step?[C].SEG Technical Program Expanded Abstracts,2015,34:115-119.
[3] Gestel J,Heureux E,Sandschaper J.Atlantis “Beyond 4D” ocean bottom nodes acquisition design[C].SEG Technical Program Expanded Abstracts,2015,34:125-129.
[4] Sergio G,Russell E.Mirror imaging of OBS data[J].First Break,2007,25(11):37-42.
[5] White J E,Lindsay R B.Seismic waves:Radiation,transmission,and attenuation[J].Physics Today,1967,20(2):74-75.
[6] Godfrey R J,Kristiansen P,Armstrong B,et al.Imaging the Foinaven ghost[C].SEG Technical Program Expanded Abstracts,1998,17:1333-1355.
[7] Ebrom D,Li X,Sukup D.Facilitating technologies for permanently instrumented oil fields[J].The Leading Edge,2000,19(3):282-285.
[8] Ronen S,Comeaux L,and Miao X G.Imaging downgoing waves from ocean bottom stations[C].SEG Technical Program Expanded Abstracts,2005,24:963-967.
[9] Pica A,Manin M,Granger P Y,et al.3D SRME on OBS data using waveform multiple modelling[C].SEG Technical Program Expanded Abstracts,2006,25:2659-2663.
[10] Muijs R,Robertsson J O,Holliger K.Prestack depth migration of primary and surface-related multiple reflections,Part Ⅰ:Imaging[J].Geophysics,2007,72(2):S59-S69.
[11] Barr F J,Sanders J I.Attenuation of water-column reverberations using pressure and velocity detectors in a water-bottom cable[C].SEG Technical Program Expanded Abstracts,1989,8:653-656.
[12] 陈浩林,张保庆,秦学彬,等.海上OBC地震勘探高精度潮汐校正方法[J].石油地球物理勘探,2014,49(增刊1):1-4.CHEN Haolin,ZHANG Baoqing,QIN Xuebin,et al.High resolution tide correction method for seismic OBC prospecting[J].Oil Geophysical Prospecting,2014,49(S1):1-4.
[13] 程元方,李素闪,张文栋,等.海底电缆资料处理关键技术及其应用[J].石油地球物理勘探,2017,52(增刊2):26-31.CHENG Yuanfang,LI Sushan,ZHANG Wendong,et al.Key techniques for OBC data processing[J].Oil Geophysical Prospecting,2017,52(S2):26-31.
[14] 贺兆全,张保庆,刘原英,等.双检理论研究及合成处理[J].石油地球物理勘探,2011,46(4):522-528.HE Zhaoquan,ZHANG Baoqing,LIU Yuanying,et al.Response characteristics of dual-sensor and their application in OBC data processing[J].Oil Geophysical Prospecting,2011,46(4):522-528.
[15] 刘帅,季晓慧,卢俊,等.CPU与GPU协同并行的多分量地震数据各向异性叠前时间偏移[J].石油地球物理勘探,2019,54(1):65-72.LIU Shuai,JI Xiaohui,LU Jun,et al.Multi-component anisotropy prestack time migration based on collaborative parallel computing with CPU and GPU[J].Oil Geophysical Prospecting,2019,54(1):65-72.
[16] 吴丹,龚仁彬,王从镔,等.最小二乘叠前时间偏移在地震数据规则化中的应用[J].石油地球物理勘探,2019,54(1):36-44.WU Dan,GONG Renbin,WANG Congbin,et al.Seismic data regularization via least-squares prestack time migration[J].Oil Geophysical Prospecting,2019,54(1):36-44.
[17] 钟广见,刘大锰,冯常茂,等.OBS纵波资料镜像叠前时间偏移处理[J].热带海洋学报,2014,33(3):46-51.ZHONG Guangjian,LIU Dameng,FENG Changmao,et al.Mirroring pre-stack time migration processing for OBS P-wave data[J].Journal of Tropical Oceano-graphy,2014,33(3):46-51.
[18] Zhang Y,Gray S,Young J.Exact and approximate weights for Kirchhoff migration[C].SEG Technical Program Expanded Abstracts,2000,19:1036-1039.
[19] Dellinger J,Gray S,Murphy G,et al.Efficient two and one-half dimensional true-amplitude migration[C].SEG Technical Program Expanded Abstracts,1999,18:1540-1543.
[20] Schleicher J,Tygel M,Hubral P.3-D true amplitude finite-offset migration[J].Geophysics,1993,58(8):1112-1126.
[21] Bleistein N,Cohen J and Stockwell J.Mathematics of Multidimensional Seismic Inversion[R].Summer School in Mathematical Geophysics,Stanford University,1998.
[22] Beal E,Salo E,Corcoran C.Lessons from the deep processing ocean bottom seismic data[C].SEG Technical Program Expanded Abstracts,2014,33:3679-3684.
[23] Pacal E,Stewart R,Baysal E,et al.Seismic imaging with ocean-bottom nodes(OBN):mirror migration technique[C].SEG Technical Program Expanded Abstracts,2015,34:4039-4043.
[24] Alerini M,Traub B.Prestack depth imaging of ocean-bottom node data[J].Geophysics,2009,74(6):57-63.
[25] Muijs R,Robertsson J O,Holliger K.Prestack depth migration of primary and surface-related multiple reflections,Part Ⅱ:Identification and removal of resi-dual multiples[J].Geophysics,2007,72(2):71-76.
[26] Duan Y,Sava P.Elastic reverse-time migration with OBS multiples[C].SEG Technical Program Expanded Abstracts,2014,33:4071-4074.
[27] Xia G,Clarke R,Etgen J,et al.OBS multiple attenuation with application to the deep water GOM Atlantis OBS nodes data[C].SEG Technical Program Expanded Abstracts,2006,25:2654-2658.
[28] Amundsen L,Ikelle L,Robertsson J,et al.Wavefield decomposition of seabed node marine recordings[C].SEG Technical Program Expanded Abstracts,2013,32:146-150.
[29] Jiang Z,Yu J,Schuster G T,et al.Migration of multiples[J].The Leading Edge,2005,24(3):315-318.