鄂尔多斯盆地志靖地区长7段储层发育机理

Development mechanism of Chang 7 reservoir in Zhijing area,Ordos Basin

为探究鄂尔多斯盆地志靖地区长7段储层发育机理,采用铸体薄片、扫描电镜、压汞、黏土矿物分析等技术,对储层岩石学特征、成岩作用、成岩相进行细致研究分析。结果表明:(1)长7储层岩石类型多为长石砂岩、长石岩屑砂岩,填隙物以绿泥石和伊利石为主。(2)长7储层平均孔隙度为7.87%,平均渗透率为0.11×10^(-3)μm^(2),孔隙以粒间孔、溶蚀孔为主。(3)研究区水下分流河道、浊积岩控制储层的物性,成岩作用影响着储层渗流能力。研究结果明确了砂体变化的因素和优质储层的主控因素及分布规律。

In order to explore the reservoir development mechanism of Chang 7 member in Zhijing area of Ordos Basin,the petrological characteristics,diagenesis and diagenetic facies of the reservoir were studied and analyzed in detail by using casting thin section,scanning electron microscope,mercury injection,clay mineral analysis and other techniques.The results show that(1)Chang 7 reservoir rocks are mostly arkose and arkose lithic sandstone,and the interstitial materials are mainly chlorite and illite.(2)The average porosity of Chang 7 reservoir is 7.87%and the average permeability is 0.11×10^(-3)μm^(2),and the pores are mainly intergranular pores and dissolution pores.(3)The underwater distributary channel and turbidite in the study area control the physical properties of the reservoir,and diagenesis affects the permeability of the reservoir.The research results have clarified the factors of sand body change and the main controlling factors and distribution law of high-quality reservoir.