The Study On Gas Reservoir Of Fractured Tight Sandstone By Logging

The tight sandstone reservoir in M block of Tarim basin is characterized by strong inhomogeneity with complex pore structure,so the logging response characteristics of the reservoir are complex,and the identification of fluid Properties is relatively difficult.The reservoir fractures in M block are relatively well developed,and qualitative identification and quantitative evaluation of fractures is difficult,so the logging parameters of the reservoir has low accuracy.The qualitative and quantitative evaluation of fractures in M block is studied on the basis of calibrating imaging logging maps through the core,and the purpose of the evaluation is to achieve detailed description of fracture parameters.The calculating model of fracture permeability is established on the basis of the study on the fracture seepage mechanism,and the accuracy of the calculated fracture permeability is improved,and meet the the requirements of oilfield development.Fracture validity is evaluated through normal stress of fracture surface and the angle between the maximum principal stess direction and the fracture strike.The standard of the fracture validity grading evaluation is established.The system of the fracture validity evaluation suitable for study area is established.The log interpretation models of different formations are established on the basis of the rock petrophysics experiment,improve the accuracy of reservoir logging parameters,and meet the the requirements of oilfield development.The gas layers and water layers are effectively divided through the intersection method between resistivity and compressibility of different stress segments and the method of the identification of the fluid Properties by the nuclear magnetic resonance log.The standard of the classification of the reservoir matrix is established on the basis of the analysis data from the nuclear magnetic resonance experiment and mercury injection experiment.The layers of the single well are classified through the technique of discriminant analysis.The lower limit on the porosity and permeability and water saturation of the reservoir is confirmed through the minimum flow pore throat radius method and oil test point constraint method.On the basis of comprehensive analysis of the matrix classification evaluation and the fracture classification evaluation,the influencing factor between the matrix and the fracture is studied with testing data,the total standard of the classification of the matrix and the fracture is established,the reservoir validity in M block is comprehensively evaluated,and the logging support is provided for the work.