双曲时距方程对地震资料处理的影响
|
摘要
常规地震资料处理方法是建立在双曲时距理论基础之上的。本文主要研究了基于双曲方程的速度分析和动校正方法对叠加速度和 t0 时间的影响 ,并提出了改进的办法。首先从理论上证明水平层状介质中基于双曲方法的动校正速度随着炮检距的增大而增大 ;然后以水平层状介质为例进行了分析。结果表明 ,双曲速度分析会导致所计算的叠加速度偏大 ,动校正后的 t0 时间也偏大 ;反射波的炮检距越大 ,计算的叠加速度和 t0 时间偏差越大。采用非双曲时距方程可以减小计算误差
Traditional seismic data processing is on the basis of hyperbolic time-distance theory. The paper studied the impact of velocity analysis and NMO correction based on hyperbolic equation on stack velocity and to time and presented improvement method. First, it is theoretically proved that the correction velocity based on the hyperbolic equation increased along with the increased offset in horizontal layered medium and then the case of horizontal layered medium is analyzed. The results showed that hyperbolic velocity analysis can lead calculated stack velocity to become bigger and is also the same for the corrected to time; the larger the used offset of reflected wave is, the bigger the errors of calculated stack velocity and to time are.Using non-hyperbolic time-distance equation can reduce the calculated errors.
Traditional seismic data processing is on the basis of hyperbolic time-distance theory. The paper studied the impact of velocity analysis and NMO correction based on hyperbolic equation on stack velocity and to time and presented improvement method. First, it is theoretically proved that the correction velocity based on the hyperbolic equation increased along with the increased offset in horizontal layered medium and then the case of horizontal layered medium is analyzed. The results showed that hyperbolic velocity analysis can lead calculated stack velocity to become bigger and is also the same for the corrected to time; the larger the used offset of reflected wave is, the bigger the errors of calculated stack velocity and to time are.Using non-hyperbolic time-distance equation can reduce the calculated errors.
引文
[1] TanerM T andKoehlerF.Velocity spectra- digitalcom puter derivation and applications of velocity func-tion.Geophysics,1969,34(6):859～881
[2] TsvankinI andThom senL .Nonhyperbolic reflectionmoveout in anisotropic media.Geophysics,1994,59(8):1290～1304
[3] AlkhalifahT.Velocity analysis using nonhyperbolicm oveout in transversely isotropic media.Geophysics,1997,62(6):1839～1854
[4] 徐常练,许云,乌达巴拉.速度随炮检距变化(VVO)分析.石油地球物理勘探,1998,33(6):733～740
[5] 刘洋,魏修成.基于连续速度模型的速度分析方法,中国地球物理学会年刊.云南:云南科技出版社,2001,30
[2] TsvankinI andThom senL .Nonhyperbolic reflectionmoveout in anisotropic media.Geophysics,1994,59(8):1290～1304
[3] AlkhalifahT.Velocity analysis using nonhyperbolicm oveout in transversely isotropic media.Geophysics,1997,62(6):1839～1854
[4] 徐常练,许云,乌达巴拉.速度随炮检距变化(VVO)分析.石油地球物理勘探,1998,33(6):733～740
[5] 刘洋,魏修成.基于连续速度模型的速度分析方法,中国地球物理学会年刊.云南:云南科技出版社,2001,30
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