Reservoir Characteristics Of Gas Deposit In The Upper Paleozoic At Well-su 48 Area In Sulige Gas Field

The well-su 48 area is the key production-testing block of Changqing oil field in the achievement of increaseing reservers, building capacity and virtuous circle of resources. Drilling shows that large area of effective sand distribution in both horizontal and vertical dispersion are relatively narrow band, and reservers of single well-controlled are limited. Also, it shows low well yield as well as complex relationship between gas and water. Therefore, it has great significance to the future natural gas exploration and development in studying the reservoir characteristics and distribution pattern of the well-su 48 area.On the basis of abundant data and materials from drilling, logging, gas testing and other tests, this paper studies the petrology, physical properties, characteristics of pore structure of the 8th member of xiashihezi formation and the first member of shanxi formation in the study area, and then the reservoir evaluation is made. Studies have shown that rock types of gas reservoir are mainly light gray, brown gray quartz sandstones of Upper Paleozoic gas. Experienced compaction,cementation,replacement and dissolution,etc, the reservoir sandstone has reached the middle diagenesis B period, and the types of porosity are mainly dissoluted pore and residual intergranular pore as the main gas storage space. Microfacies, sand body distribution and diagenesis is the main factor to controlling gas accumulation, and the most favorable reservoir sand is the main channel.The results show that the types of reservoir are mainly II and III. Basically, banding reservoir are abundance in the distributary channels. The main river of lower part of the 8th member of xiashihezi formation is the best reservoir in physical properties, and the drilling rate of Sand body is the most effective one, so it is the most advantageous development layer. The reservoir property and effective sand drilled of the first member of shanxi formationand are relatively worse. Generally, upper part of the 8th member of xiashihezi formation is poorly in reservoir properties. Forecast of the five natural gas enrichment zones has great significance in the effect of development in study area.