Abstract: Analyzed the reservoir of Xujiaweizi depression Shahezi group using the casting thin sections and Xray data, determine its lithology mainly argillaceous siltstone and fine sandstone, maturity is low. According to the mercury curve analyzed Shahezi pore structure, indicating that the overall performance of the reservoir pore throat radius is small, resulting in microscale pore structure water distribution is uneven, which is the low porosity and lowpermeability lithology reservoir. The reservoir is mainly affected by the particle size and diagenesis, dissolution effectively make all kinds of pores connectivity, therefore, the research of reservoir characteristics and influencing factors are significant to oil gas exploration and development of Xujiaweizi foult depression.

Key words: Shahezi group,    ,  Reservoir characteristics,    , Pore structure,    ,  Control factors

摘要： 利用铸体薄片和X射线衍射等方法对徐家围子断陷沙河子组储层进行了分析, 确定了其岩性主要以泥质粉砂岩及细砂岩为主, 成熟度偏低。通过室内压汞实验分析了沙河子组储层孔隙结构, 表明该储层整体表现为孔喉半径小, 造成孔隙结构中微观规模的油水分布不均匀, 为特低孔、 特低渗型储层岩性油藏, 储层主要受颗粒粒度
及成岩作用等因素控制, 溶蚀作用使各类孔隙有效连通, 因此, 进行储层特征研究及影响因素确定, 有利于徐家围子断陷油气的勘探与开发。

关键词: 沙河子组,    ,  储层特征,    ,  孔隙结构,     , 控制因素