鄂尔多斯东部上古生界储层特征及控制因素

鄂尔多斯盆地上古生界主要有太2，山2，山1，盒8，盒7五个气层组，对盆地东部佳具－子洲地区的研究表明：该区储层属于低孔低渗，具有较强非均质性的孔隙型，裂缝－孔隙型碎屑岩储层，储层储集空间类型以孔隙为主，孔隙主要为粒间孔，粒间残余孔，粒内溶孔和高岭石晶间孔，较为发育的微裂缝对储层的储集性影响不大，主要改善储层的渗滤性，影响储层储渗性的主要因素包括沉积作用，成岩作用及构造作用，粗粒度和高成熟度的储层具有相对好的物性，压实作用，硅质胶结和高岭石胶结充填作用是导致储层致密的主要因素，埋藏溶蚀作用使储层得到改善；构造破裂产生的微裂缝亦对储层起到一定的改善。

Reservoir Characteristics and Controlling Factors of the Upper Paleozoic Sandstone, Eastern Ordos Basin

The Upper Paleozoic in Ordos includes four gas formations such as Tai2, Shan2, He8 and He7. Studies on them show the reservoirs are defined as the pore-type and fracture-pore type sandstone with low porosity and low permeability, as well as markable heterogeneity. The type of reservoir's pore space is mainly pore, which can be subdivided into four sorts, i.e., intergranular pore, residual intergranular, intragranular dissolved pore as well as Kaolin intercrystal pore. The widespreading micro-fracture has minor effect on changing the reservoir's pore space, but it can increase the reservoir's permeability. The main factors that control reservoirs include deposition, diagenesis and tectogenesis. The reservoir with coarser grain size and higher maturity has better porosity and permeability. It's compaction, silicon cement and Kaolin cement that account for the tight reservoir. Dissolution and tectonic micro-fracture are favorable to improve the reservoir.