SEG/EAGE盐丘和推覆体模型的波动方程三维叠前深度偏移成像

WAVE-EQUATION 3-D PRESTACK DEPTH MIGRATION FOR THE SEG/EAGE SALT AND OVERTHRUST MODEL

三维波动方程叠前深度偏移是复杂介质中进行构造成像、弹性参数反演的重要环节 .由于其技术实现不仅涉及波场延拓理论的创新 ,而且需要大规模计算 ,因而研究难度较大 .本文以实验效果的取得为目的 ,完整地实现了SEG EAEG盐丘和推覆体模型的三维波动方程辛几何算法的叠前深度偏移成像计算 .文中详细考察了所研制的波动方程三维叠前深度偏移软件系统及其对复杂地质构造的成像能力 .具体包括 :1)对于盐丘模型 ,文中讨论了成像参数的选择、地震子波对成像精度的影响、完成二维及三维叠前深度偏移的比较 ;2 )对推覆体模型 ,文中进行了脉冲响应测试 ;3)由两个模型的成像结果可见本文的波动方程三维叠前深度偏移软件系统已具有适应强速度横向变化、复杂构造的成像能力 .

The 3-D wave equation prestack depth migration is one of the most important techniques in the structure imaging and the inversion of elastic parameters of complex media. It is very difficult to deal with for the implement of this technique is related not only to the innovation of the wave field extrapolation theory but also large scale calculation. This paper is to get the result of the experiment and completely realize the 3-D symplectic wave equation prestack depth migration for the SEG/EAGE salt and overthrust model. We discuss in detail the imaging ability to a complex geologic structure using our symplectic 3-D prestack depth migration software system. It includes the selection of imaging parameters, and the effect on the migration result of the seismic wavelet and comparison with the 2-D and 3-D prestack depth migration result of the salt mode. We also present the impulse response of the overthrust model. The imaging result of the two international industrial models indicates that our software system accommodate great transversal velocity variations and complex geologic structures.