Abstract:In order to clarify the characteristics and effective reservoir genesis of deep-ultra deep tight clastic reservoir in Junggar basin, the basic characteristics and physical properties of reservoir are studied and analyzed by using the analysis and identification data of core, logging, thin section and laboratory test of more than 60 key exploration wells, so as to determine the reservoir type, characteristics, quality and effective reservoir genesis. The results show that the reservoir is mainly delta distributary channel sandbody, which can be divided into conglomerate and sandstone. It is the typical low ultra-low porosity and permeability tight clastic reservoir. The conglomerates are mainly medium conglomerates, and the gravel is mainly tuff. The content of sandstone cuttings is high. The lithology is mainly fine-grained, medium fine-grained lithic sandstone, and the cuttings are mainly tuff with low maturity. The cement is mainly carbonate and siliceous, locally enriched in laumontite and albite. Diagenesis mainly includes destructive compaction, pressure solution and cementation, and constructive dissolution. The vertical variation of pores can be divided into two types: primary pore type in the south and secondary pore type in the north. The secondary pore type can be divided into two types, that are feldspar dissolution and zeolite dissolution. The two types have different numbers of secondary pore zones in different blocks and buried depths. Favorable facies, dissolution and abnormal high pressure formed effective reservoirs.