四参数速度分析方法在新场转换波处理中的应用  

APPLICATION OF FOUR-PARAMETER VELOCITY ANALYSIS IN CONVERTED-WAVE DATA PROCESSING IN XINCHANG GAS FIELD

作　　者：马昭军[1] 唐建明[1,2] 蒋能春[1] 

机构地区：[1]中国石化西南分公司勘探开发研究院德阳分院 [2]成都理工大学能源学院,四川成都610059

出　　处：《物探化探计算技术》2008年第4期267-272,261,共6页Computing Techniques For Geophysical and Geochemical Exploration

基　　金：中国石化重点科技攻关项目资助(P05003)

摘　　要：转换波时距方程的选择直接影响转换波速度分析和动校的准确度,这里比较了Thoms-en方程、双平方根方程和LXY方程的动校精度。根据新场气田转换波资料的特点,采用四参数(Vc2、γ0、γeff和χeff)各向异性速度分析方法来估计叠加速度场。在速度分析过程中,不依赖于纵波速度,直接进行三参数估计。在转换波动校时,不同参数控制不同偏移距范围的同相轴,使转换波近、中和远偏移距同相轴完全拉平。通过对实际测线的单参数、三参数和四参数动校叠加剖面的比较,结果表明四参数动校叠加的效果最好。The time-distance equation of converted-wave impacts directly the accuracy of velocity analysis and moveout, and the moveout accuracy of Thomsen equation, DSR equation and LXY equation are compared in this paper. By analyzing the characters of converted-wave data in XinChang gas field, a four-parameter anisotropic velocity analysis method is used to estimate the stack velocity field. During velocity analysis, three parameters being independent of P wave velocity are estimated. Different parameters control different offset events in NMO correction, which makes events of near offset, middle offset and long offset flattened completely. By the comparison of stack sections of one-parameter, three-parameter and four-parameter moveout correction, the result of four-parameter is better than others.

关 键 词：转换波 时距方程 各向异性 速度分析 动校正 新场气田 

分 类 号：P631.4[天文地球—地质矿产勘探]