应用反演谱分解去除调谐效应的分频AVO技术  

FREQUENCY-DEPENDENT AVO BASED ON REMOVING TUNING EFFECT VIA INVERSE SPECTRAL DECOMPOSITION

作　　者：宁媛丽[1] 韩立国[1] 周子阳[2] 倪冬梅[1] 吕寅寅[1] 

机构地区：[1]吉林大学地球探测科学与技术学院,吉林长春130026 [2]核工业航测遥感中心,河北石家庄050002

出　　处：《物探化探计算技术》2012年第3期243-248,237,共6页Computing Techniques For Geophysical and Geochemical Exploration

基　　金：国家"973"项目(2007CB209603);国家"863"项目(2007AA060801)

摘　　要：传统的AVO分析是假设平面波入射到分开两个半空间的单界面,并没有考虑油藏厚度的影响。当地层为薄层时,调谐效应会使AVO的变化规律发生改变,影响储层的识别。谱分解能够将时间记录转换到不同频率,从而得到更多的储层信息。因此,可以利用谱分解进行分频AVO分析。在多种谱分解方法中,反演谱分解方法具有较高的时频分辨率,并且其直接得到的是反射系数谱,可去除子波的影响。依据这一特性,这里将反演谱分解方法用于去除调谐效应。根据实际薄层的物理参数和地质条件,设计不同厚度的薄层模型,正演得到合成地震道集;然后利用反演谱分解进行分频AVO分析。结果表明,该方法能够消除薄层调谐效应,同时还能避免陷频现象。Traditional AVO analysis assumes that plane wave incident on a single interface which separates two half-space,without considering the impact of reservoir thickness.When the layer is thin,the tuning effect changes the variation of AVO,then effects has the influence of correct identification of the reservoir.Inverse spectral decomposition can convert time recording to different frequency,so we can get more reservoir information.In this paper,we apply inverse spectral decomposition to AVO analysis.In a variety of spectral decomposition methods,time resolution and frequency resolution of spectral inversion are higher than others,and its direct result is reflectance spectrum,removing the effect of wavelet.Based on this characteristic,the paper used it to remove the effect of tuning effect.According to the actual physical parameters and geological conditions of thin bed,we design different thin-ben models with different thickness,and get seismic angle gathers after forward modeling.Then use inverse spectral decomposition to AVO analysis,the results show that this method can eliminate the tuning effect,while avoiding the phenomenon of notch.

关 键 词：薄层 调谐效应 陷频 反演谱分解 分频AVO 

分 类 号：P631.4[天文地球—地质矿产勘探]