高阶优化走时计算方法及在地震成像中的应用
|
摘要
本文根据水平层状介质中Snell定律的特点,提出了基于Taylor高阶展开式的优化走时计算方法。理论计算结果表明,本文所提出的高阶优化走时计算方法不仅适用于速度梯度为正的正常水平层状介质,同时,在出现负速度异常的水平介质中也有比一般Taylor展开式更高的计算精度。最后,利用本方法对川东北P区复杂山地三维地震数据进行叠前时间偏移处理,得到了较满意的结果。
Based on the Snell's law,we propose in this paper a new algorithm to calculate the seismic traveltimes using the higher order optimum Taylor seires.A numerical example shows that this method has higher accuracy in calculating the traveltimes both in the positive and negative gradient velocity models than the conventional method.We use this method for prestack time migration of seismic data acquired in the complicated mountain area of the Northeast Sichuan and obtain the agreeable results.
Based on the Snell's law,we propose in this paper a new algorithm to calculate the seismic traveltimes using the higher order optimum Taylor seires.A numerical example shows that this method has higher accuracy in calculating the traveltimes both in the positive and negative gradient velocity models than the conventional method.We use this method for prestack time migration of seismic data acquired in the complicated mountain area of the Northeast Sichuan and obtain the agreeable results.
引文
[1]Taner M T and Koehler F.Velocity spectra-digitalcomputer derivation and applications of velocity func-tions.Geophysics,1969,34(6):859～881
[2]Castle R J.A theory of normal moveout.Geophy-sics,1994,59(6):983～999
[3]Causs E,Haugen G U and Rommel B E.Large-offsetapproximation to seismic reflection traveltimes.Geo-physical Prospecting,2000,48(4):763～778
[4]Cohen J.Analytic Study of the Effective Parame-ters for Determination of the NMO Velocity Func-tion in Transversly Isotropic Media(Cwp-11).Cen-ter for Wave Phenomena,Colorado School of Mines,1996
[5]Wang H,Sun C,Martinez R.Optimized 6th orderNMO correction for long-offset seismic data.SEGTechnical Program Expanded Abstracts,2002,21:2313～2316
[6]Zhang F and Uren N.P-wave ray velocity functionssemblance analysis and NMO corrections in trans-versely isotropic media.SEG Technical ProgramExpanded Abstracts,2002,21:133～136
[7]Zhang F and Uren N.Anisotropic semblance analysisand NMO correctons for long offset data.16th ASEGConference,Adelaide,Australia(CD),2003
[8]胡中平.优化6次项NMO校正方法研究.石油地球物理勘探,2003,38(6):603～607Hu Zhongpin.Study of NMO correction method by opti-mized 6th-order term.OGP,2003,38(6):603～607
[9]Alkhalifah T.The offset-midpoint traveltime pyramidin transversely isotropic media.Geophysics,2000,65(4):1316～1325
[10]Dix C H.Seismic velocities from surface measurments.Geophysics,1955,20(1):68～86
[11]Adler F.Kirchhoff image propagation.Geophysics,2002,67(1):126～134
[2]Castle R J.A theory of normal moveout.Geophy-sics,1994,59(6):983～999
[3]Causs E,Haugen G U and Rommel B E.Large-offsetapproximation to seismic reflection traveltimes.Geo-physical Prospecting,2000,48(4):763～778
[4]Cohen J.Analytic Study of the Effective Parame-ters for Determination of the NMO Velocity Func-tion in Transversly Isotropic Media(Cwp-11).Cen-ter for Wave Phenomena,Colorado School of Mines,1996
[5]Wang H,Sun C,Martinez R.Optimized 6th orderNMO correction for long-offset seismic data.SEGTechnical Program Expanded Abstracts,2002,21:2313～2316
[6]Zhang F and Uren N.P-wave ray velocity functionssemblance analysis and NMO corrections in trans-versely isotropic media.SEG Technical ProgramExpanded Abstracts,2002,21:133～136
[7]Zhang F and Uren N.Anisotropic semblance analysisand NMO correctons for long offset data.16th ASEGConference,Adelaide,Australia(CD),2003
[8]胡中平.优化6次项NMO校正方法研究.石油地球物理勘探,2003,38(6):603～607Hu Zhongpin.Study of NMO correction method by opti-mized 6th-order term.OGP,2003,38(6):603～607
[9]Alkhalifah T.The offset-midpoint traveltime pyramidin transversely isotropic media.Geophysics,2000,65(4):1316～1325
[10]Dix C H.Seismic velocities from surface measurments.Geophysics,1955,20(1):68～86
[11]Adler F.Kirchhoff image propagation.Geophysics,2002,67(1):126～134
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