Characteristics and major controlling factors of Jialingjiang Formation reservoirs in Danfeng-Tanghe area, southern Sichuan Province

Abstract：Luzhou uplift in Sichuan basin is an important area for oil and gas exploration,and Jialingjiang Formation is the main producing formation in this area. Under the guidance of theories and methods of carbonate reservoir geology and on the basis of core observation, cast thin section analysis, SEM and analytical data of physical property and pore structure, in combination with new information and new achievements obtained recently, the authors studied in detail the petrologic characteristics of Jialingjiang Formation, the storage space type, pore features and electrical performance characteristics of Jia II1-Jia I and Jia II3 reservoirs in Danfeng-Tanghe area. Researches show that Jia II1-Jia I and Jia II3 reservoirs in the study area are mainly powder fine-crystalline and grained dolomite,and the accumulation spaces are mainly secondary pores（intergranular dissolved pores and dolomite intercrystalline pores）. The reservoirs are mainly of the pore type and the fracture-pore type. Researches show that ① the beach of platform facies controlled the distribution scale and range of the reservoir；② dolomitization constituted the basis of reservoir composition；③ karstification and tectonic action played a most important role in expanding the reservoir distribution and improving the physical character of the reservoir.