震源延迟叠加技术及应用效果

延迟叠加爆炸是针对高分辨率和深层地震勘探而提出来的一种激发方式。这种激发方式能在保证地震分辨率的前提下有效提高地震波能量 ,在地震波的入射角范围内 ,有效克服非球形炸药激发引起的地震波传播的方向性。应用弹性波动力学对多级延迟爆炸进行理论研究 ,结合实际试验资料 ,研究了延迟爆炸情况下激发参数对地震波能量、主频、频宽等的影响。从几何地震学出发 ,分析了不同时间激发的地震波在地下空间中的干涉情况 ,对其能量传播的方向性进行了研究。理论分析和试验效果表明 ,延迟叠加震源与相同药量的普通震源相比 ,激发地震波的主频高 ,频带宽 ,增强了下传能量 ,降低了次生干扰 ,在高分辨率和深层地震勘探中具有明显的优势。

The delay stack explosion technique and its applications

Delay stack explosion technique was developed for high-resolution and deep seismic exploration. This technique can effectively enhance the energy of seismic waves without harm to the frequencies of seismic waves, and improve the propagation directivity of seismic waves in the range of incident angles. The effects of shooting parameters on the energy, dominant frequency, and bandwidth of seismic waves were studied by combining theoretical study of multiple stage delay stack explosion with field tests. The interference of seismic waves shot at different time and the propagation directivity of energy were studied from geometry seismology. Theory analysis and field tests showed that the seismic waves shot with delay stack seismic source are high in dominant frequency as well as energy, and wide in bandwidth, compared to conventional seismic sources with the same charges. Therefore, the new seismic source is suitable for high resolution and deep seismic exploration.