相位移法高频补偿稳定性研究
|
摘要
地震波在实际介质中的传播机制与其在理想弹性介质中不同,此时其携带的机械能被部分存储、部分耗损,使得地震波发生频散现象,在近地表疏松介质中这种吸收效应更为强烈,造成大沙漠区地震勘探得到的资料分辨率降低。为了有效提高地震资料的分辨率,对疏松介质的吸收效应进行合理补偿势在必行。但其能量补偿因子是一与频率有关的幂函数,随着地震波传播距离增大和频率提高而急剧加大,计算过程不稳定,进而产生大量人为假象。通过数值模拟研究了计算不稳定性的形成机制,在前人研究基础上,提出了保持计算稳定性条件。数值模拟和实际资料处理结果表明,在保持数值计算过程稳定、高频信号不发生畸变的前提下,应用相位移法可以最大限度地恢复被地层吸收、衰减的有效高频信号,合理地提高了地震资料的垂向分辨率。
The great difference exists between the propagation of wave motion in elastic media and the real media,the mechanic energy associated with the wave motion is absorbed by the media and the frequency dispersion happens as the wave motion passes through the media,the affection is intense in loose media.To improve the resolution of seismic data efficiently,the compensation to the absorption of the loose media should be applied.The phase shift compensation procedure may cause instability and generate undesirable artifacts in the solution as the compensation factor is an exponential function of frequency and travel time.The mechanism of the instability is studied by mathematical modeling,and the stable condition of the calculation is pointed out.The mathematical modeling of seismic energy absorption and compensation of wave propagation in loose media is studied with the phase shift technique in F-X domain based on the propagation mechanism of wave motion in elastic-viscid media.The results of modeling and real seismic data show that the absorption of energy of high frequency can be recovered and the temporal resolution of seismic data is improved efficiently without the aberrance of high frequency signal with the method presented in the paper.
The great difference exists between the propagation of wave motion in elastic media and the real media,the mechanic energy associated with the wave motion is absorbed by the media and the frequency dispersion happens as the wave motion passes through the media,the affection is intense in loose media.To improve the resolution of seismic data efficiently,the compensation to the absorption of the loose media should be applied.The phase shift compensation procedure may cause instability and generate undesirable artifacts in the solution as the compensation factor is an exponential function of frequency and travel time.The mechanism of the instability is studied by mathematical modeling,and the stable condition of the calculation is pointed out.The mathematical modeling of seismic energy absorption and compensation of wave propagation in loose media is studied with the phase shift technique in F-X domain based on the propagation mechanism of wave motion in elastic-viscid media.The results of modeling and real seismic data show that the absorption of energy of high frequency can be recovered and the temporal resolution of seismic data is improved efficiently without the aberrance of high frequency signal with the method presented in the paper.
引文
[1]俞寿朋.高分辨率地震勘探[M].北京:石油工业出版社,1993.
[2]Sheriff R E,Geldart L P.Exploration seismology[M].Cambridge University Press.1995.
[3]余嘉顺,曹俊兴,鲍新毅,等.表面低速层对勘探地震横波波形影响的模拟研究[J].成都理工大学学报(自然科学版),2003,30(6):583-587.
[4]凌云.大地吸收衰减分析[J].石油地球物理勘探.2001,36(1):1-8.
[5]凌云,高军,张汝杰.基于一维阻尼波动理论的沙丘Q吸收补偿[J].石油地球物理勘探,1997,32(6):795-803.
[6]Sams M,Goldberg D.The validity of Q-estimates from borehole data using spectral ratios[J].Geophysics,1990,55(1):97-101.
[7]Pujol J M,Luschen E,Hu Y.Seismic wave attenuation in metamorphic rocks from VSP data recorded in Germany′scontinental super-deep borehole[J].Geophysics.1998,63(2):354-365.
[8]Pan C.Spectral ringing suppression and optimal windo-wing for attenuation and Q measurements[J].Geophys-ics,1998,63(2):632-636.
[9]Dasgupta R,Clark R A.Estimation of Qfrom surface seis-mic reflection data[J].Geophysics,1998,63(6):2120-2128.
[10]Hargreaves N D,Calvert A J.Inverse Q filtering by Fou-rier transform[J].Geophysics,1991,56(2):519-527.
[11]Wang Yang-hua.Quantifying the effectiveness of stabi-lized inverse Q filtering[J].Geophysics,2003,68(1):337-345.
[12]李亚林,贺振华,黄德济,等.岩石孔渗特性与地震波衰减、传播速度的相互关系[J].天然气工业,2001,21(4):7-11.
[13]Shatilo A P,Sondergeld C,Rai C S.Ultrasonic attenua-tion in Glenn Pool rocks,northeastern Oklahoma[J].Geophysics,1998,63(2):465-478.
[14]Mavko G,Mukerji T.Bounds on low-frequency seismic velocities in partially saturated rocks[J].Geophysics,1998,63(3):918-924.
[15]Wang Yanghua.A stable and efficient approach of in-verse Q filtering[J].Geophysics,2002,67(2):657-663.
[16]Kjartansson E.Constant Qwave propagation and attenua-tion[J].Geophys.RES.,1979,82(B7):4737-4748.
[17]杜增利,施泽进,徐峰,等.近地表疏松介质吸收补偿的数学模拟研究[J].西南石油大学学报,2007,29(1):44-46.
[2]Sheriff R E,Geldart L P.Exploration seismology[M].Cambridge University Press.1995.
[3]余嘉顺,曹俊兴,鲍新毅,等.表面低速层对勘探地震横波波形影响的模拟研究[J].成都理工大学学报(自然科学版),2003,30(6):583-587.
[4]凌云.大地吸收衰减分析[J].石油地球物理勘探.2001,36(1):1-8.
[5]凌云,高军,张汝杰.基于一维阻尼波动理论的沙丘Q吸收补偿[J].石油地球物理勘探,1997,32(6):795-803.
[6]Sams M,Goldberg D.The validity of Q-estimates from borehole data using spectral ratios[J].Geophysics,1990,55(1):97-101.
[7]Pujol J M,Luschen E,Hu Y.Seismic wave attenuation in metamorphic rocks from VSP data recorded in Germany′scontinental super-deep borehole[J].Geophysics.1998,63(2):354-365.
[8]Pan C.Spectral ringing suppression and optimal windo-wing for attenuation and Q measurements[J].Geophys-ics,1998,63(2):632-636.
[9]Dasgupta R,Clark R A.Estimation of Qfrom surface seis-mic reflection data[J].Geophysics,1998,63(6):2120-2128.
[10]Hargreaves N D,Calvert A J.Inverse Q filtering by Fou-rier transform[J].Geophysics,1991,56(2):519-527.
[11]Wang Yang-hua.Quantifying the effectiveness of stabi-lized inverse Q filtering[J].Geophysics,2003,68(1):337-345.
[12]李亚林,贺振华,黄德济,等.岩石孔渗特性与地震波衰减、传播速度的相互关系[J].天然气工业,2001,21(4):7-11.
[13]Shatilo A P,Sondergeld C,Rai C S.Ultrasonic attenua-tion in Glenn Pool rocks,northeastern Oklahoma[J].Geophysics,1998,63(2):465-478.
[14]Mavko G,Mukerji T.Bounds on low-frequency seismic velocities in partially saturated rocks[J].Geophysics,1998,63(3):918-924.
[15]Wang Yanghua.A stable and efficient approach of in-verse Q filtering[J].Geophysics,2002,67(2):657-663.
[16]Kjartansson E.Constant Qwave propagation and attenua-tion[J].Geophys.RES.,1979,82(B7):4737-4748.
[17]杜增利,施泽进,徐峰,等.近地表疏松介质吸收补偿的数学模拟研究[J].西南石油大学学报,2007,29(1):44-46.
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