Offset-domain common image gathers on wave equation assisted by attribute migration
LIU Guofeng1, LI Haibo2, LIU Yu1, MENG Xiaohong1
1. School of Geophysics and Information Technology, China University of Geosciences(Beijing), Beijing 100083, China; 2. Geophysical Prospecting Team of Shandong Bureau of Geology, Jinan, Shandong 250104, China
Abstract:Seismic migration based on wave equation is more accurate than Kirchhoff-based migration,and the former is more sensitive to the accuracy of a velocity model.Therefore,instead of Kirchhoff depth migration,it is of important practical significance for velocity iteration of offset-domain common image gathers based on wave equation.A computation scheme based on attribute migration is proposed to analyze offset-domain common image gathers through wave equation migration.In other words,migration is done after modulating surface offset,then the ratio of the migration based on modulated offset to the migration based on original data is taken as the surface offset of an imaging point.By giving new migration to its corresponding offset,and calculating and stacking literately,the final result is surface offset gathers.In practice,the two kinds of migration are performed during the same migration circle,and the computing effort is only increased by 30% since only increasing the propagation of receiver wavefield.2D and 3D model and field data have proved the method effective.
YilmazÖZ.SeismicDataAnalysis,Processing,Inver-sion and Interpretation[M].Society of Exploration Geophysicists,2001,https://doi.org/10.1190/1.9781560801580.
[2]
Bednar J. A brief history of seismic migration[J]. Geophysics,2005,70(3):3MJ-20MJ.
[3]
吴帮玉,杨辉,孙文博,等.三维共偏移叠前地震数据反假频射线束形成偏移成像[J].地球物理学报,2018,61(8):3297-3309.WU Bangyu,YANG Hui,SUN Wenbo,et al.Common offset 3D prestack seismic data anti-aliasing beamforming migration and imaging[J].Chinese Journal of Geophysics,2018,61(8):3297-3309.
[4]
柯璇,石颖.基于一步法波场延拓的正演模拟和逆时偏移成像[J].地球物理学报,2017,60(11):4468-4479.KE Xuan,SHI Ying.Forward simulation and reverse time migration imaging based on one step wavefield extrapolation[J].Chinese Journal of Geophysics,2017,60(11):4468-4479.
[5]
陈生昌.基于反射波动方程的地震反射数据波形成像[J].石油地球物理勘探,2018,53(3):487-501.CHEN Shengchang.Seismic reflection data waveform imaging based on reflection wave equation[J].Oil Geophysical Prospecting,2018,53(3):487-501.
[6]
李庆洋.T分布起伏地表最小二乘逆时偏移[J].石油地球物理勘探,2019,54(5):1075-1083.LI Qingyang.Least-squares reverse time migration on undulated surface based on T-distribution[J].Oil Geophysical Prospecting,2019,54(5):1075-1083.
[7]
程玉坤,刘建红,周振晓,等.速度建模特色技术的实际应用[J]. 石油地球物理勘探,2017,52(增刊2):110-115.CHENG Yukun,LIU Jianhong,ZHOU Zhenxiao,et al.Depth-domain velocity model building for prestack depth imaging[J].Oil Geophysical Prospecting,2017,52(S2):110-115.
[8]
刘定进,胡光辉,蔡杰雄,等.高斯束层析与全波形反演联合速度建模[J].石油地球物理勘探,2019,54(5):1046-1056.LIU Dingjin,HU Guanghui,CAI Jiexiong et al.A joint velocity model building method with Gaussian beam tomography and full waveform inversion for land seismicdata[J].Oil Geophysical Prospecting,2019,54(5):1046-1056.
[9]
Sava P and Fomel S.Angle-domain common gathers by wavefield continuation methods[J].Geophysics,2003,68(3):1065-1074.
[10]
Sirgue J,Jousselin P and Audebert F.Understanding wave-equation images gathers:A prerequisite for advanced post-processing and velocity model building[C].Extended Abstracts of 72nd EAGE Conference & Exhibition,2010,437-441.
[11]
Xu S,Zhang Y and Tang B.3D angle gathers from reverse-time migration[J].Geophysics,2011,76(2):S77-S92.
[12]
Montel J and Lambare G.RTM and Kirchhoff angle domain common-image gathers for migration velocity analysis[C].SEG Technical Program Expanded Abstracts,2011,30:3120-3124.
[13]
Yang Z,Huang S,Yan R.Improved subsalt tomography using RTM surface offset gathers[C]. SEG Technical Program Expanded Abstracts,2015,34:5254-5258.
[14]
Zhao Y and Zhang H.Cost reduction of RTM surface offset gathers by local coherent events based interpolation[C].SEG Technical Program Expanded Abstracts,2015,34:4587-4590.
[15]
Ehinger A,Lailly P,Marfurt K.Green's function implementation of common-offset,wave-equation migration[J]. Geophysics,1996,61(6):1813-1821.
Zhang G and Zhang M. Common-image gathers in the offset domain from reverse-time migration[J].Journal of Applied Geophysics,2014,103:99-103.
[18]
Bleistein N. On the imaging of reflectors in the earth[J].Geophysics,1987,52(7):931-942.
[19]
Nguyen S,Baina R,Alerini M,et al.Stereo tomo-graphy assisted by migration of attributes[J]. Geophysical Prospecting,2008,56(5):613-625.
[20]
Giboli M,Baina R,Opera L,et al. Reverse time migration surface offset gathers:Part 1-A new method to produce "classical" common image gathers[C]. SEG Technical Program Expanded Abstracts,2012,31,http://dx.doi.org/10.1190/segam2012-1007.1.
[21]
Lemaistre L,Lencrerot R,Jousselin P,et al. Reverse time migration surface offset gathers part 2:using the full power of wide azimuth information[C]. SEG Technical Program Expanded Abstracts,2012,31:http://dx.doi.org/10.1190/segam2012-0421.1.
[22]
Schuster G. Reverse-time migration=generalized diffraction stack migration[C]. SEG Technical Program Expanded Abstracts,2002,21:1280-1283.
[23]
Stolt R H,Benson A K.Seismic migration:theory and practice//Handbook of Geophysical Exploration[M]. Geophysical Press,1986,London.
[24]
Liu H,Li B,Liu H,et al. The issue of prestack reverse time migration and solutions with graphic processing unit implementation[J].Geophysical Prospecting,2012,60(5):906-918.
[25]
Clapp R. Reverse time migration with random boun-daries[C]. SEG Technical Program Expanded Abstracts,2009,28:2343-2347.
[26]
Liu G,Meng X,Ni J,et al. Evaluation of the 2D reflection seismic method toward the exploration of thrust-controlled mineral deposits in southwestern Fujian Province,China[J].Geophysics,2018,83(4):B209- B220.
[27]
Liu G,Meng X,Liu Y.Depth migration with the near surface:A case study for mineral exploration in China[J]. Interpretation,2019,7(4):T809-T817.