相位叠加技术及其在弯线资料处理中的应用

Phase stacking technique and its application in curved line data processing

1. 石油大学勘探系,东营 257062;2. 中国新星石油公司东北石油局,长春 130062

Department of Exploration, University of Petroleum, Dongying 257062

地震波经过地下介质的透射、反射和吸收作用,使反射波发生时间延迟、相位畸变、振幅衰减。这些因素对各个地震道是不一样的,且往往是时变的。其结果造成在CDP道集或共反射面元叠加时,由于各道的不一致性而影响叠加效果,使信噪比和分辨率不能得到有效提高。常规的剩余静校正方法由于计算量大,在实际应用中受到一些限制；并且它只校正剩余时差部分,而不考虑相位的畸变和振幅的不一致性。本文介绍的这种简便相位叠加方法,在CDP道集或共反射面元道集叠加之前,能够使各道的剩余时差得到校正,同时还进行相位校正反振幅一致性校正,从而达到同相叠加的目的。文中首先给出了相位叠加的基本原理及实现过程,最后给出了两个例子．一个是对普通二维测线的处理结果,一个是对弯曲测线共反射面元叠加的处理结果。结果表明,相位叠加技术简便、快捷、实用,可作为传统水平叠加方法的一种补充方法。相位叠加的实质是在共反射面元内同时完成剩余静校、常相位校正和振幅一致性校正,值得注意的是,这里的常相位校正中的相位值对各个道是变化的。

Seismic wave will lead to time delay,phase distortion,and amplitude decay as a result of thetransmission,reflection and absorption of subsurface media. The factors are different for each seis-mic trace and are time variant. They will influence the effect of CDP gathers or bin stacking because of the non-uniformity of each trace. The conventional residual static correction method requires large computation amount,onlycorrects the residual moveout and disregards the phase distortion and amplitude non-uniformity,So the method is restricted in real application. In the paper,a Simply phase stacking method is intro-duced,which can correct the residual moveout of each trace and perform phase correction and amplitude umiformity correction before the CDP gathers or bin stacking to achieve the goal of in-phase stacking.The basic principle and implementation precedure of the phase stacking techmque are given inthe paper. Two examples are also given. One is the processing result for the common 2-D lines, theother is the Processing result of the bin stacking for the curved lines. The results demonstrate thatthe technique is simlile. fast and practical, and can be an additional method for the conventionalhorizontal stacking. In substance,the phase stacking is to simultaneously finish residual static correction,constantphase correction,and amplitude uniformity correction in a bin. It is worth noticing that the phasevalue in the constant phase correction is varying for each trace.