The Application And Research Of Induced Polarization Method In Exploration Of A Copper Polymetallic Mine In Yunnan

Induced polarization method is widely used metals in the Exploration of metal mineral,because of the characteristics of high resolution and high efficiency, it has been unanimously affirmed. In the dual frequency IP method, apparent amplitude frequency P and Apparent resistivity were usually used for geological deduction in the past, butsometimes it did not work. So we define a new parameter called apparent IP ratio J by multiplicating and dividing P and ρ which is integrated with the information of apparent amplitude frequency and apparent resistivity. Apparent IP ratio can effectively suppress irrelative anomalies to the electronic conductor.so as to bring about the precision to the interpretation. Applied to the appraisal of a copper polymetallic mine in Yunnan IP anomalies, We expect to separate the ore-related Anomalies from barren ones by extracting secondary information of the sectional data,It proves useful in the practical work.The theory of finite element method for modeling and least-squares inversion theory is introduced in the first in this article. And in order to study the feasibility of apparent IP ratio J,The theory of finite element method is used to establish a forward model, After observing obvious effects,,the author applies apparent IP ratio J to copper polymetallic mine in Yunnan for the appraisal of the dual frequency IP anomalies, after a comprehensive survey of Amplitude-frequency induced polarization in this mining, we obtain the P and ρ measured data of the study area. And analyze the anomaly characteristics of the two parameters 。In order to obtain apparent IP ratio we divides the P by ρ.Depending on the anomalous character of IP ratio, we find out three species parameter exception features of similarities and differences, Studying the effect of reflected characteristics of field sources.Through the analysis of physical parameters and geological survey in the study area, it reflects that the anomalous character of valid exceptions in the area is low resistivity and high polarization.Basing on the value of P and ρ from the comprehensive survey, we delineate three exceptions:Y1、Y2、Y3.According to the anomalous character of the J,We can assume the anomalous character of Y1 anomaly zone is high resistance high polarization, while the anomalous character of Y1 and Y2 anomaly zone is low resistance high polarization. In order to determine scope, depth and occurrence of the abnormal band polarization bodies,we assign precision measuring profiles in remarkably clear and continuous space, Implementing High power intermediate gradient method, magnetic method and dipole- dipole amplitude frequency induced polarization sounding and inversing the bathymetric data by least-squares inversion theory and drawing the contour map. According to the characteristics of the geological condition and physical property data, we try an interpretation and inference.Based on the analysis in the comparison of three kinds of parameters anomalies. At the same time, Combined with the Analysis in characteristics of the geological and physical parameters of the study area, the conclusion was as follows: the mineralization phenomenon of two low resistivity and high polarization bands in this district is relatively common and enriching mineralization “storage layer”— alteration sandstone and silty slate strata exposed widely, so the author speculates that the possibility of mineralization exist obviously; the anomaly of high resistivity and high polarization that is composed of a high resistivity body(shallow quartz vein) or the dual electrical layers formed by electrolyte belongs to the Solid conductor and the surrounding solution; The apparent IP ratio J has a good effect on Highlighting the significance and Suppressing interference anomalies.