广角反射子波的估算及应用

The estimation and application of wide-angle reflection wavelet

1. 中国地质大学资源学院,湖北武汉 430074;2. 江苏油田,江苏扬州 225000

China University of Geoscience, Wuhan 430074, China

在实际地震反射记录上,可以记录到临界角以外的反射波,这种波被称之为广角反射波或超临界角反射波。从实际地震资料出发对广角反射波的特性进行了分析:①广角反射波具有强振幅、白噪声;②广角反射波的振幅谱相对稳定;③广角反射波与临界角内反射波相比更接近于最小相位。根据上述广角反射波的特点,在地震资料处理中,利用广角反射记录估算子波,并应用于反褶积处理,改善了成果资料的品质。实际应用表明,在大炮检距观测资料的低信噪比处理时,采用这种方法可以得到更好的处理效果。

The reflected waves beyond the critical angle are often observed in the record of real seismic reflection, which is called wide-angle reflection or critical angle-exceeded reflection. There are three features by the analysis of real seismic data:① Wide-angle reflection has high amplitude and white noise; ② the amplitude spectrum of the wide-angle reflection is stable relatively; ③wide-angle reflection is closer to the minimum phase spectrum. According to the characteristics above, favorable results demonstrate the a-bility of wide-angle reflection record in wavelet estimation and deconvolution processing. The practice proves that better results are obtained when this method is applied to process the low SNR data for the current large offsets in field seismic survey.