Forward Modeling Of Hydraulic Fracture In Vertical Well By Electromagnetic Wave Logging

In order to study underground hydraulic fracture,this paper carries out forward simulation research based on finite element method,relying on the principle of electromagnetic wave instrument.Starting from the basic theory of electromagnetic wave logging,this paper introduces the structure and basic working principle of electromagnetic logging tool.Based on the basic principle of electromagnetic field,the electric field distribution function and the electric field boundary conditions are derived in the process of electromagnetic wave logging.In this study,COMSOL software was used to establish disc crack model,elliptical crack model,rectangular crack model and irregular crack model.On this basis,the amplitude ratio and phase difference of induction electromotive force between the receiving coils of logging tools are studied in depth.Through numerical simulation,it can be seen that the forward simulation results of fracture location are accurate;the peak phenomenon of amplitude ratio and phase difference curve is obvious;the height,length,shape of fracture,proppant conductivity and angle between fracture and borehole,logging tool frequency and source distance,borehole and mud resistivity in invasion zone have an impact on forward simulation.The simulation results show that it is feasible to use electromagnetic wave propagation logging for hydraulic fracturing detection,which has certain reference value for identifying fracture location information,judging fracture effectiveness and determining regional effectiveness of fracture system.The conclusions obtained provide a theoretical basis for hydraulic fracture detection and evaluation.