基于S变换的地震相分析技术

Seismic facies analysis based on S-transform.

1. 成都理工大学信息工程学院，四川成都610059;2. 四川石油管理局物探公司成都物探研究中心，四川成都610213;3. 中国地质大学地球物理与空间信息学院，湖北武汉430074

College of Information Engineering,Chengdu University of Technology,Chengdu 610059,China

为全面准确地描述地震相特征,在地震相分析中引入了时频分析技术,如短时窗傅里叶变换、Cabor 变换、小波变换等。之后发展起来的 S 变换时频分析方法综合了短时窗傅里叶变换和小波变换的优点,具有线性化、无损可逆性以及高时频分辨率等特性。阐述了 S 变换的基本理论,并利用 S 变换对理想的地震序列模型以及实际地震资料进行了地震相分析。通过对地震相特征的连续性以及振幅和频率变化特征的分析发现,对于规模较小的地震相体,在时间剖面上很难识别其层序内的地震相特征(特别是频率)随旅行时的变化情况,但在 S 变换的时频域内可以被清楚地体现出来。因此,在进行沉积环境识别时,可以利用 S 变换来提供有效地震信息。

S-transform,i.e.a new time-frequency analysis tool is put forward to describe seismic facies exactly.Integrating the advantage of short-time window Fourier transform and wavelet transform,S-transform has many characteristics such as linearity,lossless invertibility,high time-frequency resolution and so on.We may describe seismic facies conti- nuity and change of amplitude and frequency by S-Trans- form seismic facies analysis of the ideal seismic sequence model and actual seismic data.For small scale seismic faci- es volume,the seismic facies character change with travel- time is difficult to identify in time section,but they could be easily identified in time-frequency domain of S-trans- form.So effective seismic information is provided to identi- fy sedimentary environment.