Analysis On The Development Characterization Of Tight Oil In Shahejie Formation In Block Fan 154,Dongying Sag

In recent years,with the rapid development of economy,energy consumption is increasing day by day,the development of conventional oil and gas resources is becoming more and more difficult,and the capacity is insufficient to meet the demand in China.The contradiction between supply and demand of oil and gas is increasingly prominent.As an alternative source of oil,the unconventional tight oil reservoir has attracted more and more attention.Tight oil reservoirs have low permeability and generally it does not have natural capacity.Currently,it is mainly exhaustion developed by Fractured Horizontal Well.During the development process,problems such as production decline fast and low recovery efficiency were encountered.Therefore,in order to improve the development efficiency,it is needed to analyze the development characteristics of the tight oil in production process.In this paper,tight oil of Shahejie formation in fan 154 block,dongying sag,shengli oilfield is taken as the research object,research and summary of the characteristics of tight oil at China and abroad and the development effects of tight oil reservoirs are made,on this basis,the geological data and production development data of fan 154 block are studied.The dynamic changes of oil and water and the change characteristics of dynamic liquid level between vertical and horizontal wells in fan 154 block are analyzed.In this paper,the Arps decline rule is used to calculate the decline rate of production,and the division of development stages and the calculation of oil recovery are carried out.Through the study,the following results and understandings were obtained:（1）The average porosity of fan 154 block in Dongying sag is 15.7%,the average permeability is 0.51×10^-3μm²,it belongs to the tight sandstone reservoir..（2）The production and development capacity of the vertical well in fan 154 area is poor,and the output declines rapidly.After two years of production,the average daily oil production is one ton,and the production curve shows the two-stage feature of"production decline-low production stability".The effect of water flooding development is not ideal.（3）Horizontal well production decline rate is slower than relative vertical Wells,the average single well in the first three years accumulative total output is four times than vertical wells,the production curve is characterized by"rapid decline-decline transition-slow decline".The injected water has a great influence on the development and output of horizontal wells.According to the yield and the changing characteristics of dynamic liquid level,the water injection efficiency of horizontal wells can be divided into three categories:strong,medium and weak.（4）The decrease rule of Arps has a good applicability to the decline stage of tight oil production in fan 154 area,and the fitting error is less than 5%.The empirical formula and curve decline method were used to predict the final recovery rate of 8.8%,and the total oil production is 268,000 tons.（5）The development effect of tight oil in fan 154 block is mainly influenced by well type,completion method,horizontal section length,number of fracture sections,construction quality,and water injection and production system.