海上地震资料零相位化处理技术研究

在海洋地震资料采集中,气枪震源子波接近最小相位子波,反射信号的峰值点并不代表地下反射界面,需要进行相位处理。传统的最小相位化处理技术不能彻底消除相位对资料的影响,传统反褶积方法从地震资料中提取零相位化算子并对资料进行零相位化处理技术,由于提取算子的不稳定性,很难得到满意的处理效果。为此,探讨了采用震源模拟子波、远场实测子波和海底提取子波求取零相位化算子并对地震资料进行零相位化处理的技术。首先分析了非零相位处理对后续高分辨率处理和解释标定的影响;然后讨论了海洋地震资料子波的获取方式,阐明了在深水、浅水两种条件下如何利用不同子波进行零相位化算子求取和应用;最后以海洋资料处理为例,证实了深、浅水资料零相位化处理技术的可靠性。

Zero-phase processing and its application on marine seismic data

In marine seismic data acquisition,the wavelet of airgun source is close to minimum phase wavelet.As we all know,the peak of the reflection isn’t represent the impedance interface,therefore,phase processing is necessary.Conventional minimum phase processing technique cannot thoroughly remove the impact of phase on the seismic data.Meanwhile,conventional deconvolution extracts zero-phasing operator and carry out zero-phase processing on the data,and it is hard to obtain satisfactory processing results because of the unstable operator.Therefore,the zero-phasing processing technique was studied based on the zero-phasing operators derived from source simulated wavelet,far field measured wavelet and sea bottom extracted wavelet to implement zero-phase processing.Firstly,the influence of non-zero-phase processing on subsequent high-resolution processing and calibration was analyzed.Then,the methods of wavelet extraction were discussed and elaborated how to use different wavelet in zero-phase operator extraction and application in shallow water and deep water.The application results on shallow and deep water seismic data verified that this method could get reliable zero-phase seismic data.