1. College of Earth Sciences, Chengdu University of Technology, Chengdu 610059, China;
2. State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation, Chengdu University of Technology, Chengdu 610059, China

The characteristics and densification factors of 2th member of Sangonghe Formation in block 1 of central Junggar Basin are studied by means of core observation, well log analysis and thin section identification. The results show that the reservoirs are mainly developed in submerged distributary channel, river mouth bar and distal bar. Reservoir rocks are mainly composed of feldspar lithic sandstone and lithic sandstone. Reservoir spaces mainly consist of secondary dissolved pores and a few primary pores, which demonstrates pore-fracture type reservoir. The development of reservoir is dually controlled by sedimentary facies and diagenesis. Strong compaction and calcite cementation are crucial factors of densification, while the late buried dissolution is a key controlling element of quality improvement. High-quality reservoir mainly develops in submerged distributary channel sand with coarse-grain, weak compaction, low calcite and strong dissolution.