起伏地表地震波场定向照明方法

基于惠更斯-菲涅尔原理和组合震源理论,提出了起伏地表情况下地震波场定向照明分析方法。该方法根据地表起伏形态和给定的照明方向进行坐标系变换,在新坐标系中计算组合震源的激发延时并模拟起伏地表定向的地震波场,从而得出地震波场源-检定向照明度。简单的二维起伏速度模型和起伏的Marmousi模型数值试验验证了该方法的有效性,表明通过坐标变换进行地震波场定向照明分析在地表起伏的勘探区域具有较大的适用性和灵活性,可以用来分析地下复杂构造对照明能量分布的贡献。

Method on directional seismic illumination on rugged surface

Based on the Huygens－Fresnel principle and the source array theory，a method of directional seis- mic illumination on the rugged surface is proposed． This method rotates coordinates in accordance with the topogra- phy of the rugged surface and the required direction of seismic illumination． According to the new coordinates，bi- directional seismic illumination can be achieved by calculating the excitation delay of the source array and the direc- tional seismic wave field． The numerical examples on a simple 2D velocity model and the rugged Marmousi model have verified the validity of this method． The results indicate that calculating the directional seismic illumination by rotating coordinates is practical and flexible in the exploration areas with a rugged surface． Besides，it can be ap- plied to analyze the influence of underground complicated geological body on the distribution of seismic energy．