复杂地表低信噪比地震数据处理研究
|
摘要
焉耆盆地地质条件复杂,侏罗纪末燕山运动和第三纪喜山运动的挤压推覆作用在焉耆盆地南缘霍拉山前形成一系列推覆构造.由于地形起伏大,近地表结构复杂,采集的地震资料信噪比较低;以推覆构造为主体的地下地质复杂性给地震成像造成极大的困难.针对该复杂地区低信噪比地震资料,在偏移前资料预处理中,通过采取一系列旨在提高信噪比、重建反射信号的技术,为后续的复杂构造成像处理奠定基础.针对断裂交错的复杂推覆构造成像,采用增强高波数波场成像的半解析Fourier地震偏移方法,能很好地成像强速度对比下的陡倾角大断裂地质构造,有效突出推覆体构造的空间形态,改善推覆体下的成像效果.
Geological conditions in Yanqi basin are very complex.The extrusion and overthrow processes by both Yanshanian movement in late Jurassic and Himalayan movement in Tertiary lead to a series of thrust nappe structures at the southern edge of the basin.Seismic data acquired in this area has a very low S/N ratio due to complex near-surface conditions.Seismic imaging becomes difficult because of complex subsurface conditions with overthrust structures and faults.Seismic processing for such data focused on both data preprocessing and seismic imaging techniques.The data preprocessing with some new methods enhanced the S/N ratio of the data and rebuilt weak reflections,which laid a foundation for velocity analysis and seismic imaging.A new Fourier migration method was used to enhance highwavenumber components for imaging complex overthrust structures and faults.The resulting seismic migration sections show a significant improvement over old migration sections.
Geological conditions in Yanqi basin are very complex.The extrusion and overthrow processes by both Yanshanian movement in late Jurassic and Himalayan movement in Tertiary lead to a series of thrust nappe structures at the southern edge of the basin.Seismic data acquired in this area has a very low S/N ratio due to complex near-surface conditions.Seismic imaging becomes difficult because of complex subsurface conditions with overthrust structures and faults.Seismic processing for such data focused on both data preprocessing and seismic imaging techniques.The data preprocessing with some new methods enhanced the S/N ratio of the data and rebuilt weak reflections,which laid a foundation for velocity analysis and seismic imaging.A new Fourier migration method was used to enhance highwavenumber components for imaging complex overthrust structures and faults.The resulting seismic migration sections show a significant improvement over old migration sections.
引文
[1]李庆忠.关于低信噪比地震资料的基本概念和质量改正方向[J].石油地球物理勘探,1986,21(4):343~352.Li Q Z.The concept of low S/N seismic data and the measuresfor improving the data quality[J].Oil Geophysical Prospecting(in Chinese),1986,21(4):343~352.
[2]刘建红,孟小红,李合群.西部山地复杂地震资料处理技术研究[J].地球物理学进展,2008,23(3):859~863.Liu J H,Meng X H,Li H Q.Seimic data processing in thecomplex mountains of western China[J].Progress in Geophys-ics(in Chinese),2008,23(3):859~863.
[3]Fu L Y.Seismogram synthesis for piecewise heterogeneousmedia[J].Geophys.J.Int.,2002,150:800~808.
[4]Fu L Y.Numerical study of generalized Lipmann-Schwingerintegral equation including surface topography[J].Geophys-ics,2003,68:665~671.
[5]Duan Y,Fu L Y.Topographic scattering effects on seismicdata:from seismic numerical modeling to field acquisition[J].Australia Soc.Expl.Geophys.Expanded Abstracts of 15thASEG Mtg,2001,651~654.
[6]Wang X,Fu L Y,et al.Effects of the traction-free surfacewith a rugged topography on seismic wave propagation:nu-merical modeling[J].Exploration Geophysics,2001,32:64~70.
[7]Bevc D.Flooding the topography:Wave-equation datuming ofland data with rugged acquisition topography[J].Geophysics,1997,62:1558~1569.
[8]段玉,符力耘.利用FKSUB消除局部规则干扰波[J].石油地球物理勘探,1996,31(6):874~884.Du Y,Fu L Y.Local regular noise elimination using FKSUBmodel[J].Oil Geophysical Prospecting(in Chinese),1996,31(6):874~884.
[9]张军华,吕宁,田连玉,等.地震资料去噪方法技术综合评述[J].地球物理学进展,2006,21(2):546~553.Zhang J H,LüN,Tian L Y,et al.An overview of the meth-ods and techniques for seismic data noise attenuation[J].Pro-gress in Geophysics(in Chinese),2006,21(2):546~553.
[10]Fu L Y.Broadband constant-coefficient propagators[J].Geo-physical Prospecting,2005,53(3):299~310.
[11]Fu L Y.Comparison of different one-way propagators forwave forward propagation in heterogeneous crustal waveguides[J].Bulletin of the Seismological Society of America,2006,96:1091~1113.
[12]Reshef M.Depth migration from irregular surfaces withdepth extrapolation methods[J].Geophysics,1991,56(1):119~122.
[13]符力耘,孙伟家,李东平.退化的Fourier偏移算子及其在复杂断块成像中的应用[J].地球物理学报,2007,50(4):1241~1250.Fu L Y,Sun W J,Li D P.Degenerate migrators for imagingfault related complex structures[J].Chinese J.Geophys.(inChinese),2007,50(4):1241~1250.
[14]Stoffa P L,Fokkema J T,de Luna Freire R M,et al.Split-step Fourier migration[J].Geophysics,1990,55(4):410~421.
[15]Ristow D,Ruhl T.Fourier finite-difference migration[J].Geophysics,1994,59(12):1882~1893.
[16]Le Rousseau J H,de Hoop M V.Modeling and imaging withthe scalar generalized-screen algorithms in isotropic media[J].Geophysics,2001,66(5):1551~1568.
[17]刘喜武,刘洪.波动方程地震偏移成像方法的现状与进展[J].地球物理学进展,2002,17(4):582~591.Liu X W,Liu H.Status and Progress on Wave Equation Mi-gration Methods[J].Progress in Geophysics(in Chinese),2002,17(4):582~591.
[18]刘礼农,高红伟,刘洪,等.三维VTI介质中波动方程深度偏移的最优分裂Fourier方法[J].地球物理学报,2005,48(2):406~414.Liu L N,Gao H W,Liu H,et al..Wave equation depth mi-gration with optimum split-step Fourier method in 3-D VTImedia[J].Chinese J.Geophys.(in Chinese),2005,48(2):406~414.
[19]刘礼农,陈树民,张剑峰.稀疏采样下陡角度构造的波动方程深度偏移成像[J].地球物理学报,2006,49(5):1452~1459.Liu L N,Chen S M,Zhang J F.Steep dipping structuredepth imaging using wave equation based migration schemeson 3-D sparse dataset[J].Chinese J.Geophys.(in Chinese),2006,49(5):1452~1459.
[2]刘建红,孟小红,李合群.西部山地复杂地震资料处理技术研究[J].地球物理学进展,2008,23(3):859~863.Liu J H,Meng X H,Li H Q.Seimic data processing in thecomplex mountains of western China[J].Progress in Geophys-ics(in Chinese),2008,23(3):859~863.
[3]Fu L Y.Seismogram synthesis for piecewise heterogeneousmedia[J].Geophys.J.Int.,2002,150:800~808.
[4]Fu L Y.Numerical study of generalized Lipmann-Schwingerintegral equation including surface topography[J].Geophys-ics,2003,68:665~671.
[5]Duan Y,Fu L Y.Topographic scattering effects on seismicdata:from seismic numerical modeling to field acquisition[J].Australia Soc.Expl.Geophys.Expanded Abstracts of 15thASEG Mtg,2001,651~654.
[6]Wang X,Fu L Y,et al.Effects of the traction-free surfacewith a rugged topography on seismic wave propagation:nu-merical modeling[J].Exploration Geophysics,2001,32:64~70.
[7]Bevc D.Flooding the topography:Wave-equation datuming ofland data with rugged acquisition topography[J].Geophysics,1997,62:1558~1569.
[8]段玉,符力耘.利用FKSUB消除局部规则干扰波[J].石油地球物理勘探,1996,31(6):874~884.Du Y,Fu L Y.Local regular noise elimination using FKSUBmodel[J].Oil Geophysical Prospecting(in Chinese),1996,31(6):874~884.
[9]张军华,吕宁,田连玉,等.地震资料去噪方法技术综合评述[J].地球物理学进展,2006,21(2):546~553.Zhang J H,LüN,Tian L Y,et al.An overview of the meth-ods and techniques for seismic data noise attenuation[J].Pro-gress in Geophysics(in Chinese),2006,21(2):546~553.
[10]Fu L Y.Broadband constant-coefficient propagators[J].Geo-physical Prospecting,2005,53(3):299~310.
[11]Fu L Y.Comparison of different one-way propagators forwave forward propagation in heterogeneous crustal waveguides[J].Bulletin of the Seismological Society of America,2006,96:1091~1113.
[12]Reshef M.Depth migration from irregular surfaces withdepth extrapolation methods[J].Geophysics,1991,56(1):119~122.
[13]符力耘,孙伟家,李东平.退化的Fourier偏移算子及其在复杂断块成像中的应用[J].地球物理学报,2007,50(4):1241~1250.Fu L Y,Sun W J,Li D P.Degenerate migrators for imagingfault related complex structures[J].Chinese J.Geophys.(inChinese),2007,50(4):1241~1250.
[14]Stoffa P L,Fokkema J T,de Luna Freire R M,et al.Split-step Fourier migration[J].Geophysics,1990,55(4):410~421.
[15]Ristow D,Ruhl T.Fourier finite-difference migration[J].Geophysics,1994,59(12):1882~1893.
[16]Le Rousseau J H,de Hoop M V.Modeling and imaging withthe scalar generalized-screen algorithms in isotropic media[J].Geophysics,2001,66(5):1551~1568.
[17]刘喜武,刘洪.波动方程地震偏移成像方法的现状与进展[J].地球物理学进展,2002,17(4):582~591.Liu X W,Liu H.Status and Progress on Wave Equation Mi-gration Methods[J].Progress in Geophysics(in Chinese),2002,17(4):582~591.
[18]刘礼农,高红伟,刘洪,等.三维VTI介质中波动方程深度偏移的最优分裂Fourier方法[J].地球物理学报,2005,48(2):406~414.Liu L N,Gao H W,Liu H,et al..Wave equation depth mi-gration with optimum split-step Fourier method in 3-D VTImedia[J].Chinese J.Geophys.(in Chinese),2005,48(2):406~414.
[19]刘礼农,陈树民,张剑峰.稀疏采样下陡角度构造的波动方程深度偏移成像[J].地球物理学报,2006,49(5):1452~1459.Liu L N,Chen S M,Zhang J F.Steep dipping structuredepth imaging using wave equation based migration schemeson 3-D sparse dataset[J].Chinese J.Geophys.(in Chinese),2006,49(5):1452~1459.
版权所有：© 2023 中国地质图书馆 中国地质调查局地学文献中心