准噶尔盆地侏罗系低渗透油气储层特征及成因探讨

The Characteristics of Low Permeability Reservoir in Jurassic in Junggar Basin and Discussion of Its Origin

通过对准噶尔盆地侏罗系低渗储层岩石学特征、成岩作用特征及物性特征、孔隙结构特征等因素分析 ,研究了侏罗系低渗储层的成因 ,分析了影响低渗储层性质的重要因素 ,认为成岩压实作用是决定准噶尔盆地侏罗系低渗储层性质的关键因素 ,相对优质储层主要分布于低热成熟度、低塑性岩屑含量和粗粒级的砂体中。砂岩粒径、塑性岩屑含量和煤系发育程度影响成岩压实减孔量 ,从而影响剩余原生粒间孔隙发育程度。三工河组受沉积环境、组分和结构控制的相对优质储层分布广泛 ,是侏罗系中的最佳储层。煤系地层发育程度对储层物性有重要控制作用。

By analyzing reservoir lithology characteristics,diagenesis characteristics and physical property characteristics,pore structure characteristics in Jurassic in Junggar basin,the paper studied the origin of low permeability reservoir and factors of affecting reservoir property.It showed that diagenetic compaction is the key factor of forming low-permeability reservoir in Jurassic in Junggar,and that relatively high-quality reservoir is mainly in low thermal maturity,a little plastic clastic and coarse-grade sand bodies.The diameter of sand,content of plastic clastic and development of coal measures play a role in decreasing pore and development of protogenic pore between grains during diagenetic compaction.The Sangonghe formation,which is controlled by sedimentary situation,composition and structure,has extensive distribution of relatively high-quality reservoir and is the best reservoir in Jurassic.The development of coal measures has an important effect on reservoir physical property.