Dynamic Identification And Productivity Analysis Of Carbonate Reservoirs In Gas Reservoir B

In carbonate gas reservoirs,pores,fractures and caves of different sizes are usually developed,which makes the reservoir types controlled by gas wells significantly different,thus affecting the production performance and final productivity,and then bringing difficulties to the subsequent development of gas fields.According to the geological characteristics and production data of the target gas reservoir,based on the statistical analysis of 25 well test curves,combined with the dynamic data such as pressure history curve and meter gas recovery index curve,the carbonate reservoirs in this block are identified and classified.At the same time,the productivity evaluation methods of different types of reservoirs are discussed.In this paper,the characteristics of double logarithmic pressure curve of target gas reservoir are analyzed.The parameters of B gas reservoir are explained by three kinds of well test models: apparent homogeneity,dual medium and radial composite.Combining the well test method with the field practice,it is determined that the reservoir types corresponding to the well test model are dissolution pore type and fracture hole type.Combined with pressure recovery curve and rice gas recovery index curve,the comprehensive identification reference chart of each reservoir type is drawn.In order to solve the problem that the productivity test time of low permeability carbonate reservoir is too long,the productivity test method of "unclosed well equal time" is adopted in the mine,and the flow pressure is corrected,which effectively shortens the productivity test time of low permeability reservoir.The production capacity is calculated more accurately.The reservoir with stable production is regarded as homogeneous formation,and according to the theory of equivalent seepage resistance and the method of "hydropower similarity principle",the problem of productivity evaluation of fracture reservoir and fracture-pore type reservoir is solved.Through the application and analysis of field examples,the accuracy and adaptability of dynamic data in identifying reservoir types are verified,the problem of insufficient understanding of reservoir in static test data is solved,and the method of identification and classification of carbonate reservoir is improved.The characteristics of three kinds of reservoirs divided by dynamic comprehensive identification method are analyzed,and the method of productivity evaluation is clarified.