论文部分内容阅读
陕甘宁盆地中部马五 1 4 气层成岩相主要包括准同生期近地表大气淋蚀次生孔隙相、成岩期浅埋次生孔隙相、表生期岩溶次生孔隙相、再埋藏早期次生孔隙相、再埋藏晚期次生孔隙相和复合型次生孔隙相。不同类型成岩相的沉积学标志、地球化学特征、空间分布、演化序列和发育的控制因素不同 ,对气藏的最终形成所起的作用亦不同。其中 ,准同生期大气淋蚀次生孔隙相及成岩期浅埋次生孔隙相是形成气藏的基础 ,复合型次生孔隙相和表生期岩溶次生孔隙相是形成气藏的关键 ,再埋藏早期和晚期次生孔隙相是形成气藏的必要条件。诸类型成岩相的叠加和改造部位通常是气藏发育的最有利地区
The diagenetic facies of the MA5-1 4 formation in the central part of the Shaan-Gan-Ning Basin mainly include the secondary pore facies of near-surface atmospheric erosion in the quasi-syngenesis, the secondary pore facies in the diagenetic stage and the secondary pore facies in the karst epoch, Secondary pore phase, and then buried late secondary pore phase and complex secondary pore phase. Sedimentological signs, geochemical characteristics, spatial distribution, evolutionary sequences and developmental controlling factors of diagenetic facies of different types are different, which play different roles in the final formation of gas reservoirs. Among them, the secondary porosity phase of the atmospheric leaching in the quasi-syngenesis and the shallow secondary porosity phase in the diagenesis are the foundation for the formation of gas reservoirs. Complex secondary pore facies and superficial karst secondary pore facies are the key to the formation of gas reservoirs Then, the secondary and early secondary pore burial is the necessary condition for the formation of gas reservoirs. The superimposition and alteration of various types of diagenetic facies are usually the most favorable areas for the development of gas reservoirs