川东南地区嘉一—嘉二段储层特征及成岩作用

Reservoir Characteristics and Diagenesis of the First-second Member of Jialingjiang Formation in the Southeast of Sichuan Basin

通过野外露头及岩芯观察、薄片鉴定、物性分析等技术手段,分析了川东南地区嘉一—嘉二段储层特征、成岩作用及储层发育的控制因素。嘉一—嘉二段储层主要发育于颗粒灰岩及白云岩中,其储集空间以次生孔隙为主.孔隙度主要集中在1.00%～2.00%,平均1.64%,渗透率主要集中在0.010～0.200mD,平均0.019mD,储层物性条件较差.为典型的低孔低渗型储层。储层经历了压实、压溶作用、白云石化作用、重结晶作用、胶结充填作用、溶蚀作用、构造破裂作用以及膏化、去膏化作用等多种成岩作用的改造后,嘉一—嘉二段最终形成了大多孔隙度小于5%的储层格局。嘉一—嘉二段储层发育受沉积微相、成岩作用及裂缝(构造)的综合控制。

Based on the outdoors crop, core observation, thin section analysis, porosity testing, permeability testing and so on, analyze the reservoir characteristics, diagenesis and the reservoir controlling factors of the first-second member of Jialingjiang Formation in the southeast of Sichuan Basin in details. The reservoirs mainly exist in the grain limestone and dolomite and the reservoir space is mostly secondary pores. Porosity of the first-second member of Jialingjiang Formation is mainly between 1.00% and 2.00% with the average porosity of 1.64%; its permeability is mainly between 0.010 mD and 0.200 roD. Porosity and permeability of the First-second member of Jialingjiang Formation are low and the reservoirs are typical tight reservoir. The reservoir had suffered complicated diagenesis such as depression, pressure solution, dolomitization, recrystallization, cementation, fracture diagenesis before the porosity of reservoirs was reduced from more than 50% at the time of depositing to less than 5%. Reservoir of the first-second member of Jialingjiang Formation is controlled by the Microfacies, diagenesis and fracture.