测井曲线的小波变换特性在自动分层中的应用

研究了信号在特定函数作为小波基时其小波变换过零（极值）点的特征，提出了利用小波变换过零（极值）点特性对测井信号进行地层划分的方法．该方法包括两个主要步骤，一是利用小波变换的多分辨率特性得到测井曲线的形态特性随空间坐标的变化信息；二是利用小波变换过零（极值）点的特征在不同尺度上的反映，提取不同尺度下的奇异点作为分层的待参考点，结合实际情况最终确定分层点．并结合实际应用，验证了利用该方法处理测井信号的有效性。

WAVELET TRANSFORM PROPERTIES OF WELL LOG AND THEIR APPLICATION IN AUTOMATIC SEGMENTATION

The zero-crossing and extreme point properties of wavelet transform of signal are discussed by using a special function as mother wavelet. A new method of automatic segmentation is developed based on the extreme point properties of wavelet transform. The method consists of two main steps: 1. Using the multi-resolution properties of wavelet transform, we can get the information of shape variation with space coordination. 2. Using the extreme point properties of wavelet transform under different scales, we extract extreme point as referenced point of layer boundary and decided the final layer boundary on the basis of practical condition. Efficiency of this method in processing well log signal is examined.