速度分析中的CMP叠加道同相求和

在进行常规速度分析时,为了提高速度分析结果的信噪比,通常采用相邻若干个CMP道集作为原始数据。当地下界面倾斜时,各个CMP道集使用同一速度动校正后得到的叠加道有一定的时差。如果这些叠加道求和时能沿同相轴方向叠加,就能够最大限度地提高速度谱的信噪比和分辨率。实际地震资料试验表明,对于倾斜反射层,与常规直接求和相比,沿同相轴同相求和得到的能量可提高近两倍。

Inphase summation of CMP stack traces in velocity analysis

In conventional velocity analysis,some adjacent CMP gathers are usually used as input data so as to improve the S/N ratio of velocity analysis results. In the case of slant reflectors. time differences will exist among stack traces of the CMP gathers which have undergone NMO correction in the same velocity. The most satisfactory S/N ratio and resolution of velocity spectrum can be obtained when the stack traces are summed by inphase way. The test of field seismic data shows that in the case of slant reflectors, the stack energy obtained by inphase summation may be almost three times as high as that obtained by conventional direct summation.