斜井井间地震高斯射线束正演方法

Forward simulation method for crosswell seismic Gaussian beam of declined well

用于开展井间地震勘探的井多为斜井或水平井,使得本为二维的井间地震问题变为三维问题,常规正演方法在精度上和速度上都不能很好地满足实际生产需要。因高斯射线束方法能将波动方程法和射线追踪法很好地结合起来,首先推导了适用于斜井井间地震的高斯射线束方法原理,并利用VC++6.0和Qt环境编写了斜井井间地震高斯射线束法正演程序。利用所编软件对斜井井间地质模型进行正演模拟分析,并与常规正演方法进行对比,正演结果既有地震波的运动学特征又有动力学特征,计算速度非常快,优于常规正演方法。

The inclined wells and horizontal wells used for crosswell seismic exploration make the 2-D crosswell problem to 3-D crosswell problem,and therefore the conventional forward simulation method cannot meet the need of actual production in speed and precision. As Gaussian beam method can effectively combine wave equation method with ray tracing method,it is applied to the crosswell seismic exploration of declined wells in this paper. Firstly,the basic principle of the Gaussian beam method is derived,and then the forward program of Gaussian beam method is written in C language under the environment of VC and Qt. The forward simulation of declined well crosswell geological model is finished using the program,and the result is compared with that obtained using conventional forward simulation method. It is shown that Gaussian beam forward method has not only the kinematic features but also the dynamic features of the seismic wave. And its computation speed is higher than that of conventional forward simulation method.