共偏移距可分表示法叠前深度偏移

张致付; 刘春园; 张春涛; 孟小红

共偏移距可分表示法叠前深度偏移

张致付^{1, 2,},
刘春园³,
张春涛³,
孟小红^{1, 2}

1.
地质过程与矿产资源国家重点实验室和地下信息探测技术与仪器教育部重点实验室, 北京 100083
2.
中国地质大学地球物理与信息技术学院, 北京 100083
3.
中国石油大学地球资源与信息学院, 北京 102249

基金项目:

国家自然科学基金项目 40474047

地质过程与矿产资源国家重点实验室开放课题 GPMR200654

北京市重点学科“地球探测与信息技术” XK104910598

详细信息

作者简介:
张致付(1978-),男,博士,讲师,主要从事地震波成像与资料处理方法研究．E-mail：zhangzhf@cugb.edu.cn

中图分类号: P631.4
计量
- 文章访问数: 2549
- HTML全文浏览量: 108
- PDF下载量: 116
- 被引次数: 0
出版历程
- 收稿日期: 2007-04-12
- 刊出日期: 2007-07-25

The Offset-Domain Prestack Depth Migration with Optimal Separable Approximation

1.
State Key Laboratory of Geological Processes and Mineral Resources; Geo-detection Laboratory of the Ministry of Education, Beijing 100083, China
2.
School of Geophysics and Information Technology, China University of Geosciences, Beijing 100083, China
3.
School of Natural Resource and Information Technology, China University of Petroleum, Beijing 102249, China

摘要

摘要: 基于双平方根方程的共偏移距可分表示法叠前深度偏移用于复杂介质成像, 该方法在中点-偏移距坐标中同时向下延拓炮点和检波点波场, 实现方式采用正反傅立叶变换.构造的双平方根方程波场延拓算子能够使波数域变量与空间(速度) 域变量分离, 波数域内进行相移计算, 在空间域对因介质横向变速引起的时移作修正.地震数据偏移不需要逐炮计算, 具有较高的效率.对Marmousi模型数据的偏移成像结果显示, 该方法较好地成像强横向变速介质中的复杂构造.
- 双平方根方程 /
- 最优可分表示 /
- 叠前深度偏移
Abstract: The offset-domain prestack depth migration with optimal separable approximation, based on the double square root equation, is applied to image complex media with large and rapid velocity variations. The method downward continues the source and the receiver wavefields simultaneously. The mixed domain algorithm with forward Fourier and inverse Fourier transform is used to construct the double square root equation wavefield extrapolation operator. This operator separates variables in the wave number domain and variables in the space domain. The phase operation is implemented in the wave number domain, while the time delay for lateral velocity variation is corrected in the space domain. The migration algorithm is efficient for the seismic data and it is not computed shot by shot. The data set test of the Marmousi model indicates that the offset-domain migration provides a satisfactory seismic migration section on which complex geologic structures are imaged in media with large and rapid lateral velocity variations.
- double square root equation /
- optimal separable approximation /
- prestack depth migration

HTML全文

图 1 不同近似方法数值逼近象征的对比

Fig. 1. Numerical computation comparison of symbol with different approximate methods

下载: 全尺寸图片幻灯片

图 2 脉冲响应的比较

a, b分别是offset=200 m和400 m的理论解; c, d分别是offset=200 m和400 m的SSF法脉冲响应; e, f分别是offset=200 m和400 m的OSA法脉冲响应

Fig. 2. Comparison of impulse responses

下载: 全尺寸图片幻灯片

图 3 Marmousi模型与单炮记录

Fig. 3. Marmousi model and shot records

下载: 全尺寸图片幻灯片

图 4 Marmousi模型偏移结果

Fig. 4. Marmousi data test with OSA migration method

下载: 全尺寸图片幻灯片

参考文献(17)

[1]	Biondi, B., Palacharla, G., 1996.3-D prestack migration of common-azimuth data. Geophysics, 61: 1822-1832. doi: 10.1190/1.1444098
[2]	Chen, J. B., Liu, H., 2004. Opti mization approxi mation with separable variables for the one-way wave operator. Geo-physical Research Letters, 31: L06613.
[3]	Chen, J. B., Liu, H., Zhang, Z. F., 2007. A separable-kernel decomposition method for approxi mating the DSR continuation operator. Geophysics, 72: S25-S31. doi: 10.1190/1.2399368
[4]	Claerbout, J. F., 1985. Imaging the earth's interior. Blackwell Scientific publication, Oxford.
[5]	Gazdag, J., 1978. Wave-equation migration with the phase shift method. Geophysics, 43: 1342-1351. doi: 10.1190/1.1440899
[6]	Jin, S. W., Mosher, C. C., Wu, R. S., 2002. Offset-domain pseudoscreen prestack depth migration. Geophysics, 67: 1895-1902. doi: 10.1190/1.1527089
[7]	Le Rousseau, J. H., De Hoop, M. V., 2001. Modeling andi maging with the scalar generalized-screen algorithms inisotropic media. Geophysics, 66: 1551-1568.
[8]	Liu, L. N., Zhang, J. F., 2006.3-D wavefield extrapolation with optimum split-step Fourier method. Geophysics, 71: T95-108.
[9]	Popovici, A. M., 1996. Prestack migration by split-step DSR. Geophysics, 61: 1412-1416. doi: 10.1190/1.1444065
[10]	Ristow, D., Ruhl, T., 1994. Fourier finite-difference migration. Geophysics, 59: 1882-1893. doi: 10.1190/1.1443575
[11]	Ristow, D., Ruhl, T., 1997.3-Di mplicit finite-difference migration by multi way-splitting. Geophysics, 62: 554-567. doi: 10.1190/1.1444165
[12]	Song, J., 2001. The opti mization expression of functions and manifolds in high dimensions by ones in low dimensions. Chin. Sci. Bull. , 46: 977-984 (in Chinese).
[13]	Stoffa, P. L., Fokkema, J. T., Freire, R. M., et al., 1990. Split-step Fourier migration. Geophysics, 55: 410-421. doi: 10.1190/1.1442850
[14]	Zhang, G. Q., Zhang, Y., Zhou, H. B., 2000. Helical finite-difference schemes for 3-D depth migration. 70th Ann. Internat. Mtg. Geophys., Expanded Abstract, 19: 862-865.
[15]	Zhang, Z. F., Liu, H., Chen, J. B., 2005. Implement of optimal separable approxi mation in seismic migration. Chinese Journal of Geophysics, 48: 1422-1427 (in Chinese with English abstract).
[16]	宋健, 2001. 高维函数和流形在低维可视空间中的最优表达. 科学通报, 46: 977-984. https://www.cnki.com.cn/Article/CJFDTOTAL-KXTB200112001.htm
[17]	张致付, 刘洪, 陈景波, 等, 2005. 地震偏移的最优可分近似算法实现. 地球物理学报, 48: 1422-1427. https://www.cnki.com.cn/Article/CJFDTOTAL-DQWX200506026.htm