西湖凹陷低孔低渗储层气测录井识别技术

Gas logging identification technology of low porosity and low permeability reservoirs in Xihu sag

西湖凹陷平湖组和花岗组油气层多为凝析气或轻质油层,埋藏普遍偏深、储层物性差,且具有流动性强、极易挥发的特点,由于传统的油气层识别技术所考虑的参数均比较单一,识别效果较差,故应用统计学中判别分析方法,对西湖凹陷低孔低渗油气层进行识别。此方法同时采用5个气测敏感参数作为不同油气层性质的判别参数,建立油气层综合判别函数进行流体性质判别。通过东海西湖凹陷低孔低渗油气层的判别效果来看,油气层识别符合率较传统识别方法显著提高,有效克服了传统储层识别方法的局限性,提高了录井工作效率和识别准确性。

The hydrocarbon reservoirs of Pinghu Formation and Huagang Formation in Xihu sag are mostly condensate gas or light crude oil-producing layers,generally deep burial,poor reservoir physical properties,and have the characteristics of strong fluidity and easy volatility.Because the parameters considered by the traditional hydrocarbon reservoir identification technology are relatively single,the identification effect is poor,so the discriminant analysis method in statistics is used to identify low porosity and low permeability reservoirs in Xihu sag.In this method,five gas logging sensitive parameters are adopted as the discriminant parameters of different hydrocarbon reservoir properties,and the comprehensive discriminant function of hydrocarbon reservoir is established to discriminate fluid properties.Judging from the discriminant effect of low porosity and low permeability reservoirs in Xihu sag,East China Sea,the coincidence rate of hydrocarbon reservoir identification is significantly higher than that of the traditional identification methods,which effectively overcomes the limitations of the traditional reservoir identification methods and improves mud logging work efficiency and identification accuracy.