Research On Logging Evaluation Method For Low Porosity And Low Permeability Reservoir In B Oilfield Of Peru

Low porosity and low permeability reservoirs are characterized by small porosity,low permeability,strong heterogeneity and complex pore structure,which results in low correlation between pore and permeability,unclear characteristics of oil and water layers,difficult determination of criteria and difficult quantitative evaluation.In this paper,the low-porosity and low-permeability reservoirs in the BALLENA oilfield in Peru are the main research objects.Firstly,the basic characteristics of the reservoirs in the study area are statistically analyzed based on geological data and core data.On this basis,the four properties of lithology,oil-bearing,physical properties and logging response characteristics in the study area are analyzed.Secondly,the difference of logging data system in the study area is standardized and the core depth of coring Wells is returned.Then,the reservoirs are classified according to the flow zone index(FZI),reservoir quality index(RQI)and capillary pressure curve morphology and their characteristic parameters,which improves the correlation of reservoir porosity.According to the characteristics of reservoir low porosity,the core measurement data was analyzed by regression analysis,and the mud content,porosity,stratified permeability model and variable m saturation model were established to improve the accuracy of logging interpretation.Finally,the lower limit of reservoir physical properties was determined by oil-bearing production method,frequency statistics method and irreducible water saturation method.The reservoir classification standard was established by plotting oil and logging response data,and the key wells in the study area have been comprehensively interpreted and evaluated.It has certain significance for logging evaluation of low porosity and low permeability reservoirs in this area.