川东地区震旦系灯影组储层特征及其控制因素

采用宏观和微观相结合的 方法，通过扫描电镜、阴极发光等手段，分析川东地区震旦系灯影组钻井、岩心和露头剖面样品的镜下岩石学特征，研究川东地区震旦系灯影组白云岩储层的特征及控制因素。研究结果表明灯影组白云 岩储层主要发育在灯二段和灯四段，主要储集岩类型为微生物白云岩、颗粒白云岩和距两期风化壳0~200 m范围内的角砾白云岩和溶孔白云岩；储集空间以次生的孔、缝、洞为主，主要为粒间溶孔、粒内 溶孔、次生晶间孔、构造裂缝、溶洞等。沉积环境是影响灯二段储层发育的主要因素，其有利储集相带主要是位于水动力能量较强的或有利于造礁生物繁殖的高能颗粒滩和微生物云坪沉积环境；溶蚀作 用，特别是古岩溶作用是灯四段储层发育的主要因素。早期的桐湾运动形成了灯影组的大规模孔洞，而其后的构造运动则建立了研究区内特别复杂的孔隙－洞穴－裂缝系统。

Reservoir Characteristics and Control Factors of Sinian Dengying Formation in the Eastern Sichuan Basin

Dengying Formation of Sinian is the important gas-bearing strata in the eastern Sichuan Basin. There is important guiding significance for finding the distribution of favorable reservoir by the analysis of the reservoir characteristics and their controlling factors in the eastern Sichuan Basin. The combined macroscopic and microscopic methods are adopted for this research on Sinian Dengying Formation in the eastern Sichuan Basin. Based on the lithology characteristics, the scanning electron microscope, the cathode luminescence and some other experimental analyses, some outcrops which are taken from the outcrops and the drilling cores of Dengying Formation are studied for this paper in the eastern Sichuan Basin. The dolomite reservoir of Dengying Formation is studied in the research. The types of the dolomite reservoir formed on the 2nd Member and the 4th Member are mainly the algae dolomite, grained dolomite, powder to fine-grained dolomite and the karst breccia formed in two phase of the weathering crust of 0 to 200 m. The algae dolomite is the main reservoir rock types in the study area among them. The types of reservoir space are very complex, in which primary pore space didnt be found, and there are mainly secondary holes, seams and holes. The types of reservoir space are mainly intergranular dissolved pore, intragranular dissolved pore, secondary intergranular pores and structural fractures and caves, etc, and the intergranular dissolved pore is the main pore types among them in the study area. The development of the dolomite reservoir is mainly controlled by sedimentary environment, diagenesis and tectonic action, etc. The main factor influencing the 2nd Members reservoir development is sedimentary environment, and another important factor which stores the raw holes is the dissolution diagenetic epigenesis, especially the ancient karstification is the main factor for the 4th Member’s reservoir development. Recrystallization and dolomitization play a positive role for the formation and preservation of pore, while the cementation is the main factors of reservoir damage lower’s porosity. In addition, Tongwan Movement formed the early group of the large hole, and the later tectonic movement established the particularly complex pore-cave fracture system in the research area.