关键词: 玛湖凹陷, 砾岩储层, 储层分类, 构建饱和水T₂谱, 含油性评价

Abstract: Considering that reservoir physical property and oil-bearing property are controlled by diagenesis and sedimentation, resistivity logging is diffi cult to evaluate oil-bearing in this kind of reservoir. Considering that reservoir physical property and oil bearing property are controlled by diagenesis and sedimentation the reservoirs are divided into four types by using porosity and clay content. The saturated water T₂ spectrum and mercury injection experiments are used to establish the transformation relation between the capillary pressure and the T₂ relaxation time in large and small pores according to the reservoir types. The constructed T₂ spectrum of saturated water is formed by the transformation relation. By comparing the saturated water T₂ spectrum with the NMR logging T₂ spectrum, the apparent oil-bearing porosity and oil-sensitive factors are extracted to form a fl uid property identifi cation chart. The oil saturation model is established by using oil sensitive factors according to reservoir types. The relative error between the calculated oil saturation and the sealing coring saturation is 8.65%, which meet the requirement of precision of logging interpretation.