低孔渗储层饱和度模型应用效果对比

低孔渗储层岩石孔隙结构复杂,其饱和度评价一直是测井领域亟待解决的难点问题。研究大庆朝-长地区F油层组储层物性、泥质体积分数、孔隙等,得出该地区F油层组储层具有孔渗低、泥质含量高、微孔隙发育、束缚水饱和度高的储层特征。针对该区储层特征,利用有效介质导电理论,建立有效介质导电模型,并给出改进印度尼西亚方程和改进DOLL方程。分析三种模型及阿尔奇方程的理论特点,并用以计算三口密闭取心井的含水饱和度。对比结果表明,有效介质导电模型考虑因素全,计算的含水饱和度平均相对误差低,适合低孔渗泥质砂岩储层的含油气饱和度评价。

Comparison of saturation models in application for low porous and permeable reservoirs

Saturation evaluation of complex pore structures in reservoirs with low porosity and perme- ability remains a tough challenge in logging field. The investigation into the characters of porosity, perme- ability, shale content and pore structure in F formation of Chao-Chang area of Daqing concludes that the reservoirs are characterized by low porosity, low permeability, high shale content, more microscopic cap- illary pores and high irreducible water saturation. This paper introduces a symmetrical effective medium conductance theory based on the reservoir characters of F formation, and proposes a new effective medium conductivity model. The paper presents an improved Indonesia saturation equation and Doll equation and describes an analysis of the theoretical characteristics of three models and Archie equation and comparison of the calculated saturation results from the four models with the results in three sealed coring well. The contrast shows that the effective medium conductivity model, capable of more consideration factors, and with the minimum average relative error of water saturation, lends itself better to evaluation of the hydro- carbon saturation in argillaceous sandstone reservoir with low porosity and permeability.