基于小波变换和时频分析的地层层序划分

Stratigraphic sequence division based on the wavelet transform and time-frequency analysis

高精度层序地层学研究的关键是各级层序界面的识别与确定。测井数据小波变换技术及时频分析技术与传统的层序划分方法相比,具有一定的优越性,为高精度层序地层的定量划分提供依据。本文以营子街地区高精度层序地层格架建立为例,综合运用地震和测井资料,借助测井连续小波变换和地震时频分析技术确定具有等时意义的层序界面。应用结果表明,两种方法各有优劣,小波变换的方法精确度更高,时频分析不受曲线限制,适用性更广,两者结合能更精确地划分层序。

The key of high resolution sequence stratigraphy analysis is the identification and the definition of the sequence boundary in different levels. Compared with the traditional sequence division, the wavelet transform of log information and time- frequency analysis have much superiority, and provide the basis for the high resolution quantitative sequence division. In the paper the high resolution sequence division in Yingzijie area of Huimin sag is taken as an example. The sequence interfaces which have the significance of equitime are defined by the log information continuous wavelet transform and seismic time-frequency analysis combined with the seismic data and log information. The results show that two methods have their own advantages and disadvantages： the wavelet transform has higher accuracy and the time- frequency analysis do not limited by curves and has a wider applicability. The sequences could be divided accurately by the combination of the two methods.