叠前三维共反射面叠加在实际地震资料处理中的应用  

Application of Pre-3D common reflection surface stack in real seismic data

作　　者：覃天 沈水荣 彭文绪 

机构地区：[1]中海石油国际公司,北京100010

出　　处：《地球物理学进展》2014年第3期1257-1261,共5页Progress in Geophysics

摘　　要：针对复杂地表地质条件下地震资料覆盖次数不均、部分数据缺失而导致的地震资料品质下降、陡倾角地区成像质量变差等问题,文中采用了叠前三维共反射面叠加技术.共反射面叠加是一种与宏观速度无关且考虑了反射点曲率的地震成像方法.它利用共反射点道集一个邻域内(菲涅尔带)道之间的相关性,并将相干区域内道集的能量相加来增强地震反射信号和绕射波能量,并借助于相邻CMP道集数据形成CRS超道集,使得面元内的覆盖次数更加均匀;同时利用超道集的高覆盖次数来压制噪声,最终得到高信噪比道集数据.实际地震资料处理表明,该方法可大幅度地提高地震资料信噪比和分辨率,增强地震同相轴的连续性,此外还可为叠前偏移成像处理、AVO属性分析、叠前地震反演等提供高质量的输入数据.Data missing and folds uneven because of complex surface condition lead to the decline of seismic data quality and poor imaging.In order to resolve this kind of problem,pre-3D Common Reflection Surface（pre-3DCRS）Stack method was used.3DCRS stack is a macro-model independent seismic imaging method and takes also the local curvature of the reflector at the reflection point into account.Based on the similarity of common reflection point（CRP）trace gathers in one coherent zone（Fresnel zone）,CRS stack effectively improves S/N ratio by using more CMP trace gathers to stack.Compared with conventional CMP stack and DMO stack,CRS stack can focus more energy in the vicinity of the reflector.Application of the comprehensive processing methods by means of pre-3DCRS on real seismic records,the results showed an excellent performance.It not only improves the resolution of seismic section and the signal-to-noise ratio in deeper layers but also enhances the continuity of reflection events.Moreover,pre-3DCRS can provide higher quality pre-stack dataset for prestack migration,AVO attributes analysis and pre-stack seismic inversion.

关 键 词：三维地震 共反射面叠加 叠前地震资料处理 地震成像 信噪比 

分 类 号：P631[天文地球—地质矿产勘探]