Keywords: 
• source control theory /
• geochemistry /
• gas accumulation /
• tight sandstone gas /
• Permian Shihezi and Shanxi Formations /
• Sulige gas field /
• Ordos Basin /
•  /

Abstract: Tight sandstone gas reservoirs are distributed over a wide area in the western Sulige gas field,with interconnected and superposed gas-bearing sands. The main gas-bearing sands occur in the eighth member of the Shihezi Formation and the first member of the Shanxi Formation. These are sand bodies of a river delta sedimentary system. In this study,the geochemical characteristics of the gas from the study area were analyzed together with the characteristics of the source rocks and hydrocarbon generation in the basin to determine the gas accumulation characteristics and the extent to which the gas-water relationship is controlled by the source rocks. It is shown that the gas in the study area mainly migrated from SW to NE,from west to east,and from bottom to top. It was found that the study area,which is located within the triangular zone of three high-intensity hydrocarbon generation centers,produces abundant gas, not only from the three hydrocarbon generation areas but also in the study area itself,which is continually producing gas to this day. The effect of the source rocks is that,as the gas migrates and accumulates,it drives formation water northward and upward regionally. The general pattern in the study area is summed up as "southern gas and northern water, more water above and less below".