在地震勘探中,高速地层的屏蔽作用往往使地震波的能量难以继续向下传播,因此常规的地震资料采集方法很难得到高速屏蔽层以下地层的有效反射地震资料。根据Snell定理和Zoeppritz方程,通过水平层模型的正演模拟,研究了地震波在地层分界面上的能量与方位角关系,发现了地震反射波的能量在超临界角突然增强的变化规律。基于该能量传播规律,采用大炮检距地震采集系统对含高速屏蔽地层的理论模型进行了地震采集实验,在超临界角区域接收高速屏蔽层下方的反射地震信号,有效地削弱了高速地层的屏蔽影响。此外还研究了激发频率与分辨率的关系,对含高速屏蔽层地区的地震资料采集工作提出了一些建议。

In the seismic exploration,it is difficult for the seismic wave to transmit the shielding layer of high velocity,so it is difficult to acquire efficient seismic data of reflected wave from the stratum below the high velocity shield layer by the conventional methods.According to Snell law and Zoeppritz equation,the paper studies the rule of energy’s distribution of elastic wave on the interface,obtain the rule of received energy variation with offset or angle,and also study the relation of the exploding.