面向目标靶区的双程波动方程地震定向照明分析

提出一种面向目标靶区的地震定向照明分析技术,即采用双程声波波动方程传播算子,通过地震波传播的波印廷矢量(Poynting vector)分析对每个质点的波场值进行方向性分解,根据分解后的波场值分别计算出模型在不同方向上的地震波能量分布,最终计算出地震波震源的定向照明度。数值模型试验结果表明：利用定向照明度可以定量地分析出地震波沿不同方向传播的能量分布规律,进而分析各个不同方向的定向照明度对目标靶区照明量的贡献情况,为地震采集设计中合理地选择加密炮点的激

发位置以及激发方向提供参考依据。该方法计算速度快且精度高,对复杂的模型具有一定的适用性。

Based on two-way acoustic wave equation propagators,for a point particle,we implement a target-oriented seismic directional illumination analysis by the directional decomposition of wavefield in the time domain through Poynting vector analysis.Directionally decomposed wavefield values can be applied to calculate the energy distribution of seismic wave in different directions respectively.Finally,the directional illumination of seismic wave source can be obtained.The results of directional decomposition in the numerical model test demonstrate that the directional illumination analysis method can be used to quantitatively analyze the energy distribution regularities of seismic wave propagating in different directions.Furthermore,we can obtain the level of contribution from different directions in the target area,and this method is useful for the selection about the shooting position and direction of the densified shotpoints in seismic data acquisition. Meanwhile,the method has the advantagesof high-efficiency & high-precision and is also suitable for complex models.