复杂地表有限差分波动方程向上基准面校正

对于地表高程变化剧烈、近地表速度很高的山地地震数据，采用常规高程静校正已不能满足基准面校正处理的要求，而波动方程基准面校正则可以实现准确的基准面校正。波动方程基准面校正采用两步法来实现，即先在共炮点道集上将检波点延拓到基准面，然后在共检波点道集上将炮点延拓到基准面。给出了非水平地表速度模型和模拟西部某地区复杂地表速度模型的2个算例，应用频率空间域有限差分算子进行了波场延拓。非水平地表速度模型的波场延拓结果表明，算法是可行的；复杂地表速度模型的计算结果表明，向上波动方程基准面校正方法能够正确地消除复杂近地表结构对数据的影响。分别对向上波动方程基准面校正和常规高程静校正后的数据进行了叠加处理和叠后深度偏移处理，结果表明，经过向上波动方程基准面校正后的成像结果较之常规高程静校正结果更为精确。

Upward wave equation datum correction by finite difference scheme from complex surface.

To the seismic data acquired in the mountainous area, of which the surface elevation varies intensely and the ve- locity near the surface is high,the conventional elevation static correction cannot meet the request of the datum cor- rection;only the wave equation datum correction can real- ize it exactly.Wave equation datum correction is based on the classical two steps methods,propagating the datum to the datum surface in the CSP gather and CRP gather suc- cessively.The result of the calculation with the finite difference algorithm in the frequency-space domain,which is based on the complex surface model,indicates that the upward wave equation datum correction could remove the effect of the complex structure near the surface.The result based on upward wave equation datum correction could im- age the underground structure more correctly in comparison with the one based on elevation static correction.