胡尖山油田长9段储层孔隙结构表征及影响因素分析

通过岩心观察、普通薄片、铸体薄片、扫描电镜以及压汞测试等分析手段，对胡尖山油田长9段储层岩石学、物性和孔隙结构表征及控制因素等方面进行研究。研究表明，长9段储层岩性以岩屑长石砂岩和长石岩屑砂岩为主，储集空间以剩余粒间孔为主，喉道较细，物性较差，属于低孔低渗储层。利用分形维数结合压汞参数对储层孔隙结构进行表征，基于此将目的储层划分为4类，建立不同类型储层测井响应，明确不同类型储层的平面分布。认为沉积和成岩作用控制孔隙结构的形成，其中沉积作用是影响储层孔隙结构的先决条件，而成岩作用是决定储层孔隙结构特征的关键因素。压实和胶结作用对孔隙结构起破坏作用，溶蚀作用则改善储层孔隙结构。以上研究成果对研究区长9段储层的分类评价及下一步的油气勘探具有指导意义。

Analysis on pore structure characterization and controlling factors of 9th member of Yanchang Formation in Hujianshan Oilfield

Petrologic characteristics, physical properties and pore structure characteristics of 9th member of Yanchang Formation were studied by means of core observation, normal thin section and casting thin section, SEM and mercury injection test. The result shows that the lithology of 9th member of Yanchang Formation is dominated by feldspar lithic sandstone and lithic sandstone, the main reservoir space is remaining intergranular pores with fine pore throat, and the reservoirs are characterized by low porosity and low permeability. The reservoir pore structure can be characterized by fractal dimension and parameters of mercury injection test, and reservoirs can be divided into 4 types, all of which characters were generalized, and plane distribution of different reservoir types were drawn. The formation mechanism and controlling factors of various pore structure types are discussed in sedimentation and diagenesis. It is demonstrated that the sedimentation are the prerequisite conditions affecting the reservoir pore structure, while the types of diagenesis and its evolution sequence are the key factors for determining the pore structure characteristics. Compaction and cementation have bad affection on pore structure, while dissolution has good affection. The above research results can provide guidance for the reservoirs and for the 9th member of Yanchang Formation further gas exploration in the study area.