一种新的分炮检距动校正方法  

A new NMO approach by separate offsets

作　　者：谭俊敏[1] 陈雨红[2] 

机构地区：[1]中国石化石油勘探开发研究院处理解释中心 [2]中国科学院地质与地球物理研究所

出　　处：《石油地球物理勘探》2007年第3期263-267,共5页Oil Geophysical Prospecting

摘　　要：速度分析和动校正技术在地震资料处理中至关重要,常规动校正方法基于双曲线方程,没有考虑动校正速度随炮检距变化的影响,因而动校正结果往往不佳,从而影响叠加和成像效果。非双曲线方程具有更高的近似精度,但在进行速度分析时,由于参数较多,因而不便于进行交互处理。本文提出一种新的动校正方法,在不同的炮检距组道集上分别进行常规速度分析,用高次曲线拟合分段双曲线,最后用高次曲线方程进行动校正。理论记录实验表明:该方法比常规动校正方法效果好,与高次曲线形式动校正方法效果相近,且只需要拾取少量的速度谱,而四次曲线拟合动校正方法则需要拾取大量的速度谱;六次曲线及分式曲线拟合方法动校正制作速度谱方法既复杂,又不便于交互处理。而本文提出的方法则较好地解决了这些难题。The velocity analysis and NMO technique are very important in seismic data processing. The common NMO methods based on hyperbolic equation does not consider the influence of offsets variation on NMO velocities, therefore, the NMO results are imperfect and affect the stack and imaging effects. Non-hyperbolic equation is characteristic of higher approximate precision, but is unable to carry out interactive processing in velocity analysis because of multiple parameters. The paper proposed a new NMO approach that carries out common velocity analysis on different offsets gathers, uses high-order curves to fit separate hyperbolas and then uses high-order curves equation to carry out dynamic corrections. The tests of theoretic records showed the method is better than the common NMO method and similar to the high-order curves NMO methods but only picks up a small amount of velocity spectrum, while fourth-order curve fitting NMO method needs to pick up a great amount of velocity spectrum and sixth-order curve or fraction curve fitting methods are both complex in NMO conducting velocity spectrum and inconvenient for interactive processing. The approach presented in the paper better solved these difficulties.

关 键 词：分炮检距 速度分析 动校正 最小二乘法拟合 速度谱 

分 类 号：P631.443[天文地球—地质矿产勘探]