低对比度油层测录井综合识别方法研究与应用OACSTPCD

The accurate identification of fluid properties is critical for reservoir evaluation.However,for the Paleogene low-porosity and low-permeability reservoirs in the Lufeng area,Pearl River Mouth Basin,the low contrast between oil and water layers in conventional logs due to the presence of high-resistivity water layers complicates the identification of oil and water layers.This study first ascertained the reservoir characteristics and genetic analysis of low-contrast oil layers.Then,it developed the Flair gas logging response equation and the Flair logging response correction method,aiming to overcome the challenge that gas logging response values of low-porosity and low-permeability reservoirs are significantly influenced by factors such as drilling rate and porosity.Given the differences in the properties and components of various fluids,this study constructed new oil-bearing and water-content indices using Flair gas logging curves.Moreo-ver,this study characterized the geochemical chromatogram using a gamma probability distribution function and extracted the shape and scale factors to describe the chromatogram characteristics.Based on sensitivity parameters,this study plotted the characteristic parame-ter-based fluid property identification chart.The practical application shows that the log-based comprehensive fluid property identifica-tion method can yield satisfactory effects,achieving a compliance rate of 91.3%.Therefore,this method can be popularized.