基于小波包分解的地层吸收补偿
|
摘要
在分析地震反射波勘探信号小波包分解特性的基础上，提出了基于小波包分解的地层吸收补偿方法．如果没有地层吸收，浅层反射波和深层反射波具有相同的振幅谱而相位谱相差一线性相位．如果把地震记录分成不同的频段，不同频段对于时间的能量分布关系具有相似性，即对所有频段的深层反射的能量与同一频段浅层反射能量之比应该相同；只是不同频段的绝对能量大小不一样．由于地层的吸收造成各频段能量对时间的分布不同，如果给这些频段乘以时变权使各频段能量对时间的分布相同，就起到了对地层吸收的补偿作用．该方法首先用小波包对地震勘探信号进行分频，然后根据地层吸收的特点，在每一个频段上分别提取每一个时间点的吸收系数并用其倒数加权每一个小波包系数，再用加权后的小波包系数重构地震反射波记录消除地层吸收．该方法适合Ｑ值未知的情况，对变Ｑ和常Ｑ都能适应．从实际应用效果看，该方法能很好的补偿地层的吸收。
The Earth's filter response to seismic wave can be approximated by variable Q attenuation. A model to compensate earth filtering is developed based on the wavelet packet decomposition. According to the model, a new method to compensate earth filtering is presented. The steps of the method are : Firstly, seismic wave is decomposed into different frequency bands. Then, according to the model of compensate earth filtering, attenuation coefficients are found for each frequency component. Each wavelet packet decomposition coefficient is divided by attenuation coefficient. Finally, seismic wave is reconstructed from modified frequency components to compensate earth filtering.
The Earth's filter response to seismic wave can be approximated by variable Q attenuation. A model to compensate earth filtering is developed based on the wavelet packet decomposition. According to the model, a new method to compensate earth filtering is presented. The steps of the method are : Firstly, seismic wave is decomposed into different frequency bands. Then, according to the model of compensate earth filtering, attenuation coefficients are found for each frequency component. Each wavelet packet decomposition coefficient is divided by attenuation coefficient. Finally, seismic wave is reconstructed from modified frequency components to compensate earth filtering.
引文
[1]俞寿朋.高分辨率地震勘探.北京:石油工业出版社,1993. 162—164.
YU Shou-Peng. The High Resolution Seismic Processing (in Chinese). Beijing: Petroleum Industry Press,1993. 162-164.
[ 2 ] McCarley L A. An autoregressive filter model for constant Q attenuation. Geophysics, 1985, 50(5):749-758
[3]李庆忠.走向精确勘探的道路──高分辨率地震勘探系统工程分析.北京:石油工业出版社,1994. 89-92.
LI Qing-Zhong. The road to Precision Prospecting-High Resolution Seismic Prospecting SystemAnalysize (in Chinese). Beijing: Petroleum Industry Press, 1994. 89-92.
[ 4]张贤达.非平稳信号分析与处理,北京:国防工业出版社, 1998. 224-305.
ZHANG Xian-De. Non-Stationary Signal Analysis and Processing (in Chinese). National Defense IndustryPress, 1998. 224-305.
[ 5 ] Wong Kon Max, Wu Jingfeng, Dvidson T N, et al. Wavelet packet division multiplexing and waveletpacket design under timing error effects. IEEE Transaction on Signal Processing, 1997, 45(12):2877-2889.
[ 6 ] Saatcilar R. Coruh C. Seismic Q estimations for lithological interpretation 65,, Ann. Internat. Mtg., Soc.Expl. Geophys. Expanted abstracts. 1995. 1363-1365.
[7]李鲲鹏,刘业新,李衍达等.小波变换的过零点特性与地震勘探信号的信噪比和分辨率.地球物理学报, 1997, 40(4):561-569
LI Kun-Peng, LIU Ye-Xin, LI Yan-Da, et al. The Zero-accrossing propecties of wavelet transform andsignal noise and resolution of seismic signal. Chinese J. Geophys. (in Chinese), 1997, 40(4):560-569.
[8]章珂,刘贵忠.用遗传算法实现地震信号反褶积.地球物理学报,1997,40(4):550-560.
ZHANG Ke, LIU Gui-Zhong. Seismic deconvolution with genetic algorithms. Chinee J. Geophys. (in Chinese), 1997, 40(4): 550-560.
YU Shou-Peng. The High Resolution Seismic Processing (in Chinese). Beijing: Petroleum Industry Press,1993. 162-164.
[ 2 ] McCarley L A. An autoregressive filter model for constant Q attenuation. Geophysics, 1985, 50(5):749-758
[3]李庆忠.走向精确勘探的道路──高分辨率地震勘探系统工程分析.北京:石油工业出版社,1994. 89-92.
LI Qing-Zhong. The road to Precision Prospecting-High Resolution Seismic Prospecting SystemAnalysize (in Chinese). Beijing: Petroleum Industry Press, 1994. 89-92.
[ 4]张贤达.非平稳信号分析与处理,北京:国防工业出版社, 1998. 224-305.
ZHANG Xian-De. Non-Stationary Signal Analysis and Processing (in Chinese). National Defense IndustryPress, 1998. 224-305.
[ 5 ] Wong Kon Max, Wu Jingfeng, Dvidson T N, et al. Wavelet packet division multiplexing and waveletpacket design under timing error effects. IEEE Transaction on Signal Processing, 1997, 45(12):2877-2889.
[ 6 ] Saatcilar R. Coruh C. Seismic Q estimations for lithological interpretation 65,, Ann. Internat. Mtg., Soc.Expl. Geophys. Expanted abstracts. 1995. 1363-1365.
[7]李鲲鹏,刘业新,李衍达等.小波变换的过零点特性与地震勘探信号的信噪比和分辨率.地球物理学报, 1997, 40(4):561-569
LI Kun-Peng, LIU Ye-Xin, LI Yan-Da, et al. The Zero-accrossing propecties of wavelet transform andsignal noise and resolution of seismic signal. Chinese J. Geophys. (in Chinese), 1997, 40(4):560-569.
[8]章珂,刘贵忠.用遗传算法实现地震信号反褶积.地球物理学报,1997,40(4):550-560.
ZHANG Ke, LIU Gui-Zhong. Seismic deconvolution with genetic algorithms. Chinee J. Geophys. (in Chinese), 1997, 40(4): 550-560.
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