吐哈盆地复杂孔隙结构储层测井评价方法研究

Study on Reservoir Evaluation Method of Different Pore Structurs in Tuha Basin

目标油气层和标准水层之间孔隙结构的差异常常被忽略,导致含油饱和度计算结果偏低。从层间孔隙结构差异的成因入手,强化油藏条件下的岩电实验设计,发现复杂孔隙结构储层地层因素和孔隙度关系在双对数坐标下为非线性关系,导电规律呈现非典型阿尔奇化现象。定量分析表明层间孔隙结构差异对电阻率的影响不可忽视。不同核磁共振T2谱具有不同的岩电关系,随着孔隙结构的变差,存在岩性系数(a值)越来越大、孔隙度指数(m值)越来越小的现象。针对性地采用双孔介质的可变m值含油饱和度模型,通过试油验证,其计算结果具有较好的合理性。

The different pore structures between oil-gas layers and standard water zone are often ignored, leading to the lower calculation of oil saturation. Based on the cause of different pore structures and rock electricity experiment under the reservoir condition, it is discovered that the complex reservoir conductive rule is atypical Archie phenomenon, the formation factors and pores on double logarithm coordination is nonlinear relationship, and showing the difference of pore structures couldn＇t be ignored. Due to different NMR T2 spectrum, the worse the pore structure, the bigger value a and smaller value m, so we use the variable value rn of dual-pore structure evaluation model to calculate the oil saturation, which is more reasonable.