关键词: 非均质性, 心滩, 分支河道, 结构模态, 成岩作用, 黏土矿物, 羊三木油田

Abstract: To further understand the reservoir heterogeneity in Yangsanmu Oilfield, based on the study of facies belt and single sand body distribution, the core analysis data of cored well was used and reservoir parameters obtained by well logging and multi-well interpretation and evaluation were combined to study the heterogeneity inside, between and on the surface of reservoir in the upper reservoir group of the second member of Guantao Formation in Yangsanmu Oilfield. According to the results, the upper reservoir group of the second member of Guantao Formation in Yangsanmu Oilfield is braided river sedimentation. Due to different genesis, the heterogeneity of different microphases differs greatly. The heterogeneity of channel bar sedimentation is the strongest, and the homogeneity of branch channel sedimentation is the highest. Reservoir rock particle size and particle sorting are important parameters influencing reservoir property. Reservoir permeability is positively correlated with particle size and is inversely correlated with particle sorting. The main controlling factors of reservoir heterogeneity are reservoir structural mode, diagenesis and clay minerals. The single-mode reservoir structure has the best porosity and permeability,followed by the bimodal reservoir, and the three-mode filling reservoir has the worst porosity and permeability. The impact of diagenesis on the reservoir is actually the process of secondary pore formation and redistribution, which leads to the development of diverse pore types in the reservoir in this area and the complex compositional structure of pore genesis. The impact of clay minerals on reservoir physical properties is mainly manifested as the scattered clay minerals barely influence the reservoir, while the thin layered, bridged and filling clay minerals greatly reduce the reservoir permeability.

Key words: heterogeneity, channel bar, branch channel, structural mode, diagenesis, clay mineral, Yangsanmu Oilfield