阜康凹陷东部斜坡带二叠系储层特征及控制因素

运用岩心观察、铸体薄片鉴定、扫描电镜分析、物性测试、压汞分析等实验方法，以阜康凹陷东部斜坡带二叠系梧桐沟组储集层为研究对象，探讨其储层特征及控制因素，并对储层进行分类评价。研究表明：梧桐沟组储层以岩屑砂岩及长石岩屑砂岩为主，粒度较细，分选磨圆较差，成分与结构成熟度低；储层原生孔隙发育，具有一定量的次生溶孔及微裂缝，发育微米级孔喉，物性较好，属于中孔中低渗储层；通过研究区成岩作用类型及强度的定量分析，共识别出8种成岩相类型。研究区储层物性及孔喉结构主要受岩相及成岩相控制，共划分出29种岩相成岩相组合，结合油田实际产能，将研究区储层划分为四类，从一类到四类，储层物性、孔喉结构及产油情况逐渐变差。

Characteristics and Controlling Factors of Permian Reservoirs in Eastern Slope of Fukang Sag

The study area is located in the eastern slope of Fukang sag, Junggar basin, where the Permian reservoirs have a good exploration prospect. Through the approaches of cores observation, casting thin section identification, SEM and mercury intrusion analyses, we discussed the characteristics and controlling factors of the Permian reservoirs in the eastern slope of Fukang sag, and then conducted the reservoir evaluation and classification. The results show that, compared to the sedimentary and metamorphic rock debris, volcanic rock debris are the majority in Wutonggou Formation. The particle size is fine with poor sorting and grinding and low composition and structure maturity. Primary pores are the mainly reservoir spaces, the certain amounts of secondary dissolution pores and microfractures can also provide some spaces for hydrocarbon accumulation. The reservoir properties are dominated by moderate porosity and moderate-low permeability. Subsequently, we could recognize four types of diagenesis:compaction, dissolution, cementation and replacement in the research area. Eight types of diagenetic facies were identified through the quantitative analysis on diagenesis. The reservoir properties and pore throat structures in the research area are controlled by lithofacies and diagenetic facies, which were classified into 29 types. Based on the above analyses and combining with the actual oilfield production capacity, we divided the reservoirs into 4 types. From type 1 to type 4, the reservoir properties, pore throat structure and oil production capacity become worse and worse.