波动方程叠前深度偏移成像研究
发布时间：2019-03-31 07:51
【摘要】：波动方程叠前深度偏移成像技术是高精度高分辨率地震勘探技术的重要组成部分,主要解决具有复杂地质结构及强横向速度变化的地质体精确成像问题。相对于其他偏移方法(叠前时间偏移、叠后时间或深度偏移等),波动方程叠前深度偏移通过直接求解波动方程的数值解来进行波场延拓,在深度域叠加成像得到地下介质的深度剖面,对于构造复杂、横向速度变化剧烈的地下结构有着很好的适应性,通常能够得到较为精细的地下成像。论文详细梳理了波动方程偏移技术的发展历史及现状,介绍了偏移成像技术基本原理(偏移原理、成像原理和成像条件)。在频率波数域波场延拓(相移延拓)的基础上,利用波场分裂思想导出了裂步傅里叶算子、傅里叶有限差分算子以及广义屏算子,并在炮域实现了各算子叠前深度偏移成像。在编程实现偏移算法的过程中,分析处理了边界、数值频散、算法稳定性等关键问题,通过多种模型测试(水平模型、曲面模型、透镜体模型、Marmousi模型),验证了波动方程叠前深度偏移理论的正确性和可行性,总结了裂步傅里叶算法、傅里叶有限差分算法以及广义屏算法在理论模型偏移成像中的优缺点以及影响偏移效果的关键因素,为偏移质量控制提供了一定的参考。
[Abstract]:Wave equation prestack depth migration imaging technology is an important part of high-precision and high-resolution seismic exploration technology. It mainly solves the problem of accurate imaging of geological body with complex geological structure and strong lateral velocity variation. Compared with other migration methods (pre-stack time migration, poststack time or depth migration, etc.), wave field extension is carried out by directly solving the numerical solution of wave equation for wave equation prestack depth migration. The depth profile of underground medium can be obtained by superimposed imaging in depth domain, which has good adaptability to the underground structure with complex structure and sharp lateral velocity change, and can usually obtain more fine underground imaging. The development history and present situation of wave equation migration technology are reviewed in detail, and the basic principles of migration imaging technology (migration principle, imaging principle and imaging conditions) are introduced. On the basis of wave field extension (phase shift extension) in frequency wavenumber domain, split step Fourier operator, Fourier finite difference operator and generalized screen operator are derived by using the idea of wave field splitting, and the prestack depth migration imaging of each operator is realized in the gun domain. In the process of programming the migration algorithm, the key problems such as boundary, numerical dispersion, algorithm stability and so on are analyzed and dealt with, which are tested by various models (horizontal model, surface model, lens body model, Marmousi model). The correctness and feasibility of the wave equation prestack depth migration theory are verified, and the split-step Fourier algorithm is summarized. The advantages and disadvantages of Fourier finite difference algorithm and generalized screen algorithm in theoretical model migration imaging as well as the key factors affecting migration effect provide some reference for migration quality control.
【学位授予单位】：长安大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：P631.4
本文编号：2450712
[Abstract]:Wave equation prestack depth migration imaging technology is an important part of high-precision and high-resolution seismic exploration technology. It mainly solves the problem of accurate imaging of geological body with complex geological structure and strong lateral velocity variation. Compared with other migration methods (pre-stack time migration, poststack time or depth migration, etc.), wave field extension is carried out by directly solving the numerical solution of wave equation for wave equation prestack depth migration. The depth profile of underground medium can be obtained by superimposed imaging in depth domain, which has good adaptability to the underground structure with complex structure and sharp lateral velocity change, and can usually obtain more fine underground imaging. The development history and present situation of wave equation migration technology are reviewed in detail, and the basic principles of migration imaging technology (migration principle, imaging principle and imaging conditions) are introduced. On the basis of wave field extension (phase shift extension) in frequency wavenumber domain, split step Fourier operator, Fourier finite difference operator and generalized screen operator are derived by using the idea of wave field splitting, and the prestack depth migration imaging of each operator is realized in the gun domain. In the process of programming the migration algorithm, the key problems such as boundary, numerical dispersion, algorithm stability and so on are analyzed and dealt with, which are tested by various models (horizontal model, surface model, lens body model, Marmousi model). The correctness and feasibility of the wave equation prestack depth migration theory are verified, and the split-step Fourier algorithm is summarized. The advantages and disadvantages of Fourier finite difference algorithm and generalized screen algorithm in theoretical model migration imaging as well as the key factors affecting migration effect provide some reference for migration quality control.
【学位授予单位】：长安大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：P631.4
【参考文献】
相关期刊论文 前10条
1 撒利明;杨午阳;杜启振;王成祥;周辉;张厚柱;;地震偏移成像技术回顾与展望[J];石油地球物理勘探;2015年05期
2 李振春;;地震偏移成像技术研究现状与发展趋势[J];石油地球物理勘探;2014年01期
3 郭念民;吴国忱;;基于PML边界的变网格高阶有限差分声波方程逆时偏移[J];石油地球物理勘探;2012年02期
4 陈可洋;;完全匹配层吸收边界条件研究[J];石油物探;2010年05期
5 陈可洋;;宽频双程走时计算方法及其波场照明分析[J];勘探地球物理进展;2010年04期
6 陈可洋;;地震波逆时偏移方法研究综述[J];勘探地球物理进展;2010年03期
7 陈可洋;;地震波旅行时计算方法及其模型试验分析[J];石油物探;2010年02期
8 杨微;陈可洋;;加权吸收边界条件的优化设计[J];石油物探;2009年03期
9 陈可洋;;声波完全匹配层吸收边界条件的改进算法[J];石油物探;2009年01期
10 张宇;;振幅保真的单程波方程偏移理论[J];地球物理学报;2006年05期
相关硕士学位论文 前1条
1 张春燕;复杂条件下高效逆时偏移方法研究[D];中国石油大学;2011年
，本文编号：2450712
本文链接：https://www.wllwen.com/kejilunwen/kuangye/2450712.html
