松辽盆地腰英台油田中-低孔低渗储层孔隙结构特征及含油性

松辽盆地腰英台油田青山口组和泉头组储层为中-低孔隙度、低渗透率储层,孔隙结构复杂.在分析储层孔隙结构特征的基础上,依据孔喉分布特征,把储层分为单峰型和双峰型2大类7种亚类.单峰型:A、B类具有宽缓不对称单峰状孔喉分布且峰值对应的孔喉半径中等—偏大;C、D类是具有低幅宽缓单峰孔喉分布特征的储层,近于对称单峰孔喉分布且孔喉半径中等—偏小;E类具有不对称单峰孔喉分布且孔喉半径小.双峰型:F类具有双峰孔喉分布且峰间距较大;G类属双峰孔喉分布且峰间距小.探讨了各类储层的孔隙结构特征与含油性之间的关系.研究结果表明,在其他成藏条件相同的情况下,储层孔隙结构特征控制其含油性.其中,A、B、F类,整体含油性较好;C、D、G类含油性差;E类不含油.

Pore structure features and hydrocarbon potential of the middle-low permeability reservoir in Yaoyingtai Oilfield,Songliao Basin

The reservoirs of Qingshankou Formation and Quantou Formation in Yaoyingtai Oilfield have the characteristics of middle--low porosity,low permeability and complex pore structures.On the basis of the analysis of the characteristics of pore structure,the reservoirs are divided into two classes and seven subclasses according to the characteristics of pore throat distribution.The classes are single-peak type and double-peak type.The 7 subclasses are A type and B type——their pore throat distribution is wider and gently and there is one asymmetric peak,the pore throat radius at the peak is middle-large;C type and D type——their pore throat distribution has one wider and gently and relative symmetry peak,and the pore throat radius at the peak is middle-small;E type——its pore throat distribution has one symmetric peak and the pore throat radius is small;F type——its pore throat distribution has two peaks and the distance between them is greater;G type——its pore throat distribution has two peaks and the distance between them is smaller.The relationship between the pore structure features and hydrocarbon potential are analyzed.The analysis results indicate that when other reservoir forming conditions are the same,the pore structure features control the hydrocarbon potential of these kinds of reservoirs.A,B and F types of reservoirs have totally good hydrocarbon potential,C,D and G types of reservoirs have worse hydrocarbon potential,and F type of reservoirs have no hydrocarbon potential.