鄂尔多斯盆地中部山西组-下石盒子组储层特征

Reservoir Characteristics of Shanxi Member-Xiashihezi Member in the Central Part of Ordos Basin

鄂尔多斯盆地中部上古生界山西组-下石盒子组地层是区内天然气勘探的主要目的层。通过大量的实验分析并综合地质资料研究表明,山西组-下石盒子组岩石类型多样,孔隙类型以粒间孔、溶孔和晶间孔为主,具有低孔低渗特征;影响储集性能的因素主要有沉积作用和成岩作用,沉积作用控制储集岩体的发育和分布,成岩作用决定储集空间特征和储集性能。对储集岩进行分类评价,指导勘探的重点区域为三角洲河道砂体。

Upper Paleozoic Shanxi Member-Xiashihezi Member in the central part of Ordos Basin is a main target zone of gas exploration.Large amount of experimental analysis and geologic data study show that,Shanxi Member-Xiashihezi Member rocks have several types.Pore types are mainly intergranular pores,corroded hollows aod intercrystal pores,with the characteristics of low porosity and low permeability.The main factors affecting reservoir performance are sedimentation and diagonesis.Sedimentation controls the development and distribution of reservoir rock bodies,while diagonesis determines reservoir space characteristics and reservoir performance.Through classified evaluation on reservoir rocks,this paper indicates that the key exploration area is deltic channel sand body.