小波分析划分层序单元的地质学理论基础、方法与应用

从地质学角度对小波分析的理论基础进行了分析，认为测井曲线是地层中某种特征所反映出的不同周期沉积旋回的相互叠加，而小波分析能够将叠加在测井曲线中的不同频率的旋回识别出来。由此可以看出，对测井曲线的小波分析能够识别出其中所包含的不同周期的沉积旋回，据此可以进行层序地层单元的划分。在进行划分的过程中，小波的选取十分关键，不同的小波类型会对划分的结果产生比较明显的影响。通过对渤海湾盆地东营凹陷两口不同类型的井段进行具体的分析可以发现，该方法不仅能够划分常规的砂、泥岩互层的地层层序，同时也能够通过识别出常规方法不易识别出的一些微小特征变化、并结合Fischer图解来划分出大段单一岩性地层中的层序单元界面。

Geological concept,method and application of sequence unit dentification through wavelet analysis

Wavelet analysis as amathematic method can be used to solve some problems in sequence stratigraphy research. This paper analyzed the concept of this method from a geological standpoint and come to a conclusion that the logs are reflections of certain characteristics of strata that reveal the superposition of the sedimentary cycles in different periods，while these sedimentary cycles can be identified through wavelet analysis and used for division of sequence stratigraphic units. In practice，we realize that choosing the right wavelets are essential to the division of sequence units. We applied the technique to the analysis of different intervals of two wells in Dongying Sag of BohaiBay and found out that the method is not only useful in division of conventional interbedded sandstone and shale stratum，but also capable of identifying subtle changes that tend to be ignored with con-ventional methods. Combined with Fischer Diagram，we can use the techniques to identify the sequence units in a large interval with mono lithology.