调谐AVO的存在条件及其识别  

The existence conditions and identification of tuning AVO

作　　者：刘仕友 陈殿远 周家雄 

机构地区：[1]中海石油(中国)有限公司湛江分公司,湛江524057

出　　处：《物探化探计算技术》2015年第6期768-772,共5页Computing Techniques For Geophysical and Geochemical Exploration

基　　金：国家科技重大专项课题(2011ZX05023-004)

摘　　要：自80年代以来,AVO属性技术逐渐成为一种有效的储层预测和烃类检测技术,但是在实际应用中,AVO的复杂性、多解性也越来越为人们所熟知。叠前CRP道集,各偏移距传播路径是不同的,远近道频率也是不同,频率差异与地层耦合会产生一种调谐AVO现象。这里基于波动的叠加和干涉原理,推导了薄层的振幅响应公式,提出了调谐频率的计算公式。通过正演模型分析了调谐AVO的特征:1当地层的调谐频率高于地震资料频率时,近道调谐作用大于远道,表现为IV类异常;2当地层的调谐频率低于地震资料频率时,近道调谐作用小于远道,表现为III类异常;3当地层的调谐频率位于地震资料频率区间时,AVO特征表现为"V"特征。调谐AVO存在的基础为薄层加变化的子波频率,最后结合乐东X1目标实际例子,探索了调谐AVO的识别方法。Since the 1 980s,AVO attribute technology becomes an effective technology for reservoir prediction and hydro-carbon detection,but in practical application,the complexity and multiplicity of the AVO are more and more popular.In Pre-stack CRP gathers,different offsets have different propagation paths,and gathers of different distances have different frequen-cies.Frequency difference and stratigraphic coupling can produce a kind of tuning AVO phenomenon.Based on superposition principle and interference principle of fluctuation,formula of the thin layer amplitude response is derived,and the formula of tuning frequency is put forward.The characteristics of tuning AVO is analyzed by forward model:when the tuning frequency of the layer is higher than the frequency of seismic data,near tuning effect had more effects and it shows the AVO of class IV;when the tuning frequency of the layer is lower than the frequency of seismic data,far tuning effect had more effects and it shows the AVO of class III;when the tuning frequency of the layer is in the frequency range of seismic data,AVO feature is the"V" characteristic feature.The basis of tuning AVO is thin layer and changed wavelet frequency.In the end of the paper, the identification method of tuning AVO is explored by the evaluation of Ledong X1 target region.

关 键 词：调谐效应 AVO分析 薄互层 调谐频率 调谐厚度 

分 类 号：P631.4[天文地球—地质矿产勘探]