准噶尔盆地中佳地区佳木河组孔隙结构表征与分类评价OA

The reservoirs of the Permian Jiamuhe Formation in the Zhongjia area of the Junggar Basin are tight,where the cores are prone to fracturing due to zeolite expansion,resulting in distorted physical property data,which makes it difficult to characterize and evaluate the complex pore structures.Under the guidance of reservoir geology,qualitative and quantitative characterization of pore structures was conducted using data from casting thin sections,bulk-rock analysis,physical properties,computed tomography and high-pressure mercury intrusion.After excluding mercury intrusion data related to artificial fractures,pore throat radius and homogeneity coefficient were identified as effective parameters for characterizing pore structures and were thus selected for classification evaluation.The results show that most mercury intrusion curves exhibit an upward trend,with pore throat distributions showing"bimodal"or"unimodal"shapes.The main pore throat radius is 1.43 μm,indicating a dominance of mesopores.The main flow space accounts for 24.98％on average,less than a quarter of the total pore space.The homogeneity coefficient ranges from 0.06 to 0.37,reflecting strong heterogeneity in pore structure.Pore structures are classified into three types,with type Ⅲ being the most abundant.Reservoirs with type Ⅱ and Ⅲ pore structures are potential targets for development.