The Study Of Sedimentary Facies And Prediction Of Favorable Reservoir Zones Of Jialingjiang Formation, Qianwei Area, Sichuan Basin

Qianwei area is located in the southwest of Sichuan basin, with the controlled area of more than 5000 square kilometers. The earlier exploration results in the study area and concerned information in the neighboring area show that it has rich hydrocarbon source. And Jialingjiang Formation, Lower Triassic period, is the key potential exploration formation.Under the guidance of new principles and methods of Sedimentology and Reservoir Sedimentology, this thesis takes Jialingjiang Formation in Qianwei area as the main object of study. The petrology characteristics and sedimentary facies of nine basic wells have been studied exhaustively, from which it is deducted the depositional framework, and main types and characteristics of sedimentary facies in Jialingjiang Formation. Then four types of sedimentary facies are recognized and their facies models are established. Based on the analysis of sedimentary facies in individual wells and the correlation of three cross sections of sedimentary facies, it is elaborated that sedimentary facies of Jianglingjiang Formation are vertically and laterally developed within Qianwei area. By the method of single-factor analysis, it is pointed out facies distribution of four key formations after thorough study of four geologic factors that could embody sedimentary environment and facies, that is the thickness of formation, grainstone and dolostone, and lithofacies. With the above results, combining with reservoir and structural features, of which the emphasis is the reservoir characteristics of different rock and microfacies types, it is pointed out favorable reservoir zones, by the method of multi-factors superposition.