Heterogeneity Of N₁ Reservoir In Zhaquanquan 7 Well Area Of ??Qaidam Basin

This thesis takes the reservoir description, reservoir geology, oil field geology, logging geology and other related disciplines as the theoretical basis; adopts synthetically cores, cuttings, logging, grain size analysis, property analysis and other datas, divides the reservoir groups and small layers, combine with well log interpretation information to study the sedimentary facies, reservoir architecture and reservoir macroscopic heterogeneity of the target beds. The following results have been achieved:With the method of marker bed, sliced comparative, constant depth, Small layer have been divided and contrasted, II sand group into 12 layers, III sand group into 24 layers.The study area is shallow lake subfacies, including six microfacies:dam center, dam edge, inter-dam, beach,inter-beach. The target beds composed of dam center, dam edge and inter-dam. In macroscopic view, ?-2-3, ?-5-1 and ?-5-2 three layers with large area distribution center dam and edge dam, and the heterogeneity.are weak, ?-2-1 and ?-2-2 layers with several divided dams or beaches, and the heterogeneity are stong.The study area have six architecture elements. Four kind of inner layer superposition relationships:accretion style, transgressive style, retrogressive style and superimpose style. Four kind of splice relationships between units:dam center-dam edge, dam center-inter-dam, dam edge-inter-dam, beach-inter-beach. Totally summed 26 lithofacies, and different micro-faces have different lithofacies. The sedimentary facies patterns of the work area belongs to the the bund dam mode of shallow lake shore phase. The result shows that:?-2-3,?-5-1 and ?-5-2 three layers'architecture unit distribut stable, and have weak heterogeneity. ?-2-1 and ?-2-2 two layers architecture unit distribut unstable, and have strong heterogeneity.The permeability of work area exist various rhythmic, which most develope composite rhythm, homogeneous rhythm rarely can be found. Dam center and dam edge mainly exist composite rhythm, beach most developed normal rhythm. Interlayer have three kinds: mudstone, limestone, property. Mudstone interlayer develop extensively, others develop rarely. ?-2-2??-2-1 and ?-2-3-?-2-2 barriers' thickness is thinner, stable distribution, strong blocking ability. ?-5-2-?-5-1 barrier have small layer thickness and weak blocking ability. The frequency of dam center higher than dam edge on the whole, and zero of frequency mainly, developed in the dam center.By analyzing the inner layer heterogeneity parameters (coefficient of variation, mutation coefficient, rank difference), evaluated the heterogeneity of study layers:?-5-2 heterogeneity is weake,?-2-3 heterogeneity is moderate, ?-2-1, ?-2-2 and ?-5-1 three layers' heterogeneity is strong. The result of research on the interlayer heterogeneity shows:?-2 and III-5 two layers'interlayer heterogeneity are gradually increase outwards from the center to edge, and the heterogeneity of ?-2 is stronger than ?-5's.