Reserch On Three Dimensional Excitation Method Of Point Source

In the field of metal mineral exploration,the fixed point source induced polarization method is widely applied.In this paper,the forward modeling of three dimensional IP is carried out by using the finite element method,and the logarithmic polarization model is studied in detail,for the same model to transform the abnormal change law of the abnormal body of the power supply point analysis,the abnormal change law of the abnormal body is observed in the same model for the same power supply point.This paper introduces the basic principle of point source three dimensional induced polarization method,the geoelectric model is based on the measured data,based on the three-dimensional finite element numerical simulation program and the equivalent resistivity method,the apparent resistivity and apparent polarizability of different models are calculated.The contour maps of apparent resistivity?apparent polarizability?Arctan(Y?_s/X?_s)andArctan(Y?_s/X?_s)along different directions are plotted respectively;And the plane contour map of two directions of apparent resistivity and apparent polarizability modulus.The apparent polarizability,apparent polarizability,Arctan(Y?_s/X?_s)and the bathymetric curves of their modes in the main section are supplied by A at different locations.When the same direction of the anomalous body is the same,the power supply point A will supply different apparent resistivity and apparent polarization rate.The A of the same body at the same point of the anomalous body is fixed without moving,measuring in different directions will cause different apparent resistivity and apparent polarizability anomaly.When the power supply point A is fixed and the direction of measurement is consistent,the anomaly is related to the spatial location and distribution range of the abnormal body.In the study of the same anomaly body,the variation of the apparent resistivity and the apparent polarizability and the modes of apparent resistivity measured along the twodirections of X and Y,and the modes of the apparent polarizability of the two directions along X,Y,can be used to determine the distribution of the anomalous body in the space.Based on the actual data of a hematite mine in Sichuan,a model is established to verify the validity of the method.