基于形态学滤波与小波变换的测井曲线自动分层方法

测井曲线是了解井下地质情况(如岩性、油气层位置等)必不可少的测井资料.利用测井曲线划分地层是测井分析的首要步骤,其自动划分地层方法的研究具有重大意义.如何在分层结果中合理地剔除假地层是现今许多自动分层方法均要面对的问题.单纯的阈值设置并不能妥善处理.就此问题,本文在小波变换分层法中,提出了用形态学滤波弱化阻碍分层的因素,削弱出现假地层的可能,使得分层结果更加分明.首先将测井曲线进行形态学滤波,抹除影响分层的小直径波峰波谷,再通过小波变换模极大值法找出拟地层界面,最后综合不同的测井曲线分层结果确定最终分层结果.实验结果表明,该方法能有效减少假地层划分,使得最后的分层结果更接近真实的地层界面.

Automatic stratification method of logging curve based on morphological filtering and wavelet transform

Logging curves are indispensable logging data for understanding the geological characteristics(such as lithology,reservoir location,etc.)beneath the well.The use of logging curves to divide the formation is the first step in logging analysis,and the study of its automatic method is of great significance.How to reasonably eliminate false stratum in stratified results is a problem that many automatic stratification methods face today.Simple threshold settings are not handled properly.In this paper,in the wavelet transform layering method,the factors that weaken the stratification by morphological filtering are proposed,which weakens the possibility of pseudo-stratigraphy and makes the stratification result more distinct.Finally,different logging curves are combined to determine the final layers.The experimental results show that the proposed method can effectively reduce the pseudo-stratigraphic division,and the final stratification result is closer to the real stratum interface.