摘要
由于受测不准准则的制约,应用小波变换、广义S变换等线性算法无法同时获得高时间分辨率和高频率分辨率,而应用匹配追踪算法可克服窗函数的限制,能在时间域和频率域同时精细表征信号特征。本文在阐述地震信号匹配追踪时频谱分解的算法原理基础上,通过对标准Morlet小波进行合理改造,完备了时频原子库,有利于提高地震信号匹配分解的精度;依据Morlet小波的时宽对地震道进行开时窗,可在多个时窗内同时动态扫描匹配小波原子,可以适当提高计算效率。模型试验与实际数据分析表明,基于改进Morlet小波的地震信号匹配追踪算法更精确更高效,且具备一定的抗噪能力,适合定量分析地震资料的频谱变化特征,有助于研究储层及油气的分布范围。
Because of Heisenberg's uncertainty principle,the linear algorithms of time-frequency spectral decomposition,for example wavelet transform and generalized S transform,cannot simultaneously have high resolution in time and frequency domains.Overcoming the window function limit,the matching pursuit can precisely characterize signal features in time and frequency domains.This paper firstly discusses the algorithm theory of matching pursuit to seismic signal,and then put forward the reasonable improvement to standard Morlet wavelet,which can perfect the time-frequency atomic database,thus enhancing the precision of seismic signal matching decomposition.Based on the time-bandwidth of Morlet wavelet,the paper finally uses window treatment technology to dynamically scan matching wavelet atoms at the same time in multi-windows,so that calculation efficiency can be appropriately increasing.The model test and actual data analysis show that matching pursuit of seismic signal based on improved Morlet wavelet is more precise and efficient,and has some antinoise ability,suitable for quantitative analysis of the spectrum variation of seismic data,which will be helpful to study oil & gas reservoir distribution.
出处
《石油地球物理勘探》
EI
CSCD
北大核心
2012年第5期773-780,844+680,共8页
Oil Geophysical Prospecting
基金
国家科技重大专项"低渗透油田注水开发后渗流规律的变化特征与井网优化调整技术研究"(2011ZX05009)
"南堡凹陷油气富集规律与增储领域"(2011ZX05006-006)
国家973专项"深部有效碎屑岩储层成因机制与发育模式"(2011CB201104)联合资助
关键词
地震时频谱分解
匹配追踪算法
MORLET小波
计算效率
时频属性
seismic time-frequency spectrum decomposition,matching pursuit algorithm,Morlet wavelet,calculation efficiency,time-frequency property
