鄂尔多斯盆地瓦窑堡油田中山川区长2油层组储层特征

在长2储层岩性特征、沉积特征研究的基础上,以压汞实验、薄片鉴定、物性测试、扫描电镜等方法为实验手段,对储层岩石学特征、孔隙结构、物性特征及其影响因素进行分析研究。结果表明,长2储层主要以浅灰色、灰绿色块状细砂岩为主,孔隙类型都以残余粒间孔为主,次为粒间溶孔,其余为粒内溶孔、填隙物内溶孔及晶间微孔,少量的铸模孔、云母溶缝、微裂缝。其储层的孔喉分布类型主要有单峰正偏态细孔喉型、多峰分散型和单峰负偏态微孔喉型3种。影响本区储层孔隙类型的因素为沉积相、成岩作用、裂缝改造,其中沉积相及成岩作用是主要因素。

Reservoir Feature of Oil Bearing Chang-2 Bed in the Zhongshanchuan Area of Wayaobao Oilfield in Ordos Basin

Based on analysis of the depositional features of Chang-2 reservoir bed, the characteristics of lithology, diagenism, pore throat texture, physical property and its affecting factors are studied by intrusive mercury experiment, thin section determination, physical property test and scanning electron microscope observation. The result is that the components of Chang-2 reservoirs is mainly grayish and celadon fine sandstone, the combination type of pore throats is mainly residual intergranular porosity, next intergranular dissolve porosity and intergranular micro-fine throats, and few mould porosity, mica fuse corrode crevice and micro-crevice. The distribution type of pore throats may be classified into normal distribution of pore throat type with single apex, separation of pore throat type with apexes and negative distribution of micro-pore throat type with single apex. Affecting factors of reservoir are sedimentary facies, diagenesis and crevice change, and the main factors are sedimentary facies and diagenesis.