-
摘要: 利用检波点能量与震源能量比值构造衰减系数,研究波场各频率成分在自相关与反褶积两类成像条件中偏移成像的作用.分析检波点能量与震源能量比值分布特征,有利于克服反褶积型成像条件中分母趋于零时计算不稳定现象,也有助于平滑检波点波场与震源波场;检波点能量与震源能量比值超出正常范围容易导致偏移结果中出现照明不均匀现象.本文方法有助于改善反褶积型成像条件的偏移计算,也有助于应用照明技术指导偏移成像结果的振幅校正.Abstract: This paper discusses the migration result of different frequency wavefields in both crosscorrelation and deconvolution imaging conditions by the construction of attenuation coefficients which are based on the receiver-source energy ratio. The distribution characteristics of the receiver-source energy ratio can be used to overcome the instability in the deconcolution imaging condition if the nominator approaches to zero, and smooth both the receiver and the source wavefields. If the receiver-source energy ratio exceeds a reasonable range, it will lead to illumination irregularity in the migration results. The ideas in this paper can be used to improve the migration processing, and to guide the illumination technology of making the amplitude correction in the migration results.
-
Key words:
- Imaging condition /
- Migration /
- Attenuation coefficient /
- Attenuation factor
-
-
[1] Schultz P S, Sherwood J W C. Depth migration before stack. Geophysics, 1980, 45(3): 376-393.
[2] Claerbout J F. Imaging the earth's interior. Cambridge, MA: Blackwell Scientific Publications, 1985.
[3] 孙建国. Kirchhoff型真振幅偏移与反偏移. 勘探地球物理进展, 2002, 25(6): 1-5. Sun J G. Kirchhoff-type true-amplitude migration and demigration. Progress in Exploration Geophysics (in Chinese), 2002, 25(6): 1-5.
[4] 张关泉. 波动方程的上行波和下行波的耦合方程组. 应用数学学报, 1993, 16(2): 251-263. Zhang G Q. System of coupled equations for up-coming and down-going waves. Acta Math. Appl. Sinica (in Chinese), 1993, 16(2): 251-263.
[5] 张关泉. 波场分裂、平方根算子与偏移. // 反射地震学论文集. 上海: 同济大学出版社, 2000: 16-20. Zhang G Q. Wavefield splitting, square root operator and migration. // Collected papers on the reflection seismology (in Chinese). Shanghai: Tongji University Press, 2000: 16-20.
[6] 张宇. 振幅保真的单程波方程偏移理论. 地球物理学报, 2006, 49(5): 1410-1430. Zhang Y. The theory of true amplitude one-way wave equation migration. Chinese J. Geophys. (in Chinese), 2006, 49(5): 1410-1430.
[7] Valenciano A, Biondi B. 2D deconvolution imaging condition for shot profile migration. Expanded Abstracts of 73rd SEG Meeting, 2003, 1059-1062.
[8] Guitton A, Valenciano A, Bevc D, et al. Smoothing imaging condition for shot profile migration. Geophysics, 2007, 72(3): S149-S154.
[9] Schleicher J. A comparison of imaging conditions for wave-equation shot-profile migration. Expanded Abstracts of 77th SEG Meeting, 2007, 2393-2397.
[10] Antoine G, Valenciano A. Robust imaging condition for shot-profile migration. Expanded Abstracts of 76PthP SEG Meeting, 2006, 2519-2522.
[11] Kaelin B, Guitton A. Imaging condition for reverse time migration. Expanded Abstracts of 76th SEG Meeting, 2006, 2594-2597.
[12] Wu R S, Chen L. Mapping directional illumination and acquisition-aperture efficacy by beamlet propagators. Expanded Abstracts of 72nd SEG Meeting, 2002, 1352-1355.
[13] Rickett J E. Illumination-based normalization for wave-equation depth migration. Geophysics, 2003, 68(4): 1371-1379.
[14] Xie X B, Wu R S. Extracting angle domain information from migrated wavefield. Expanded Abstracts of 72nd SEG Meeting, 2002, 1360-1363.
[15] Sava P, Biondi B. Wave equation migration velocity analysis. I. Theory. Geophysical Prospecting, 2004, 52(6): 593-606.
[16] Soubaras R. Angle gathers for shot-record migration by local harmonic decomposition. Expanded Abstracts of 73rd SEG Meeting, 2003, 889-892.
[17] Sava P C, Fomel S. Angle-domain common-image gathers by wavefield continuation methods. Geophysics, 2003, 68(3): 1065-1074.
[18] Rickett J E, Sava P C. Offset and angle-domain common image-point gathers for shot-profile migration. Geophysics, 2002, 67(3): 883-889.
[19] Ng M. Using time-shift imaging condition for seismic migration interpolation. Expanded Abstracts of 77th SEG Meeting, 2007, 2378-2382.
-
计量
- 文章访问数:
- PDF下载数:
- 施引文献: 0
下载: