| The Changpingzi area is located in the southwest of the Yangtze block,where the NW-trending Yadu-Ziyun fault(F1)and the NW-trending Hezhang-Zunyi fault(F2)intersect.It belongs to the Pb-Zn-Ag metallogenic belt in the northwest of Guizhou,and has a good ore prospecting prospect.The geological data show that NW trending faults control the distribution of lead-zinc mineralization,and the intersection and composite site of NE,NWW and EW trending fault structures in different directions is the most favorable site for mineralization.The ore-body production is controlled by stratigraphic and tectonic conditions,and is closely related to hydrothermal activities.According to the application results of domestic and foreign prospecting methods,we take advantage of multiple methods and adopt three combined geophysical prospecting methods to carry out the prospecting work in Changpingzi area.In the study area,1:10000IP ladder scanning was carried out to delineate the IP anomaly.1:10000 ground high precision magnetic survey was carried out to find out the magnetic field distribution characteristics and the distribution of diabase in this area.On this basis,the controllable source audio-frequency magnetotelluric method and IP sounding line are deployed to further find out the deep extension of the fault structure and whether it is ore-induced anomaly.A total of 14 IP anomalies were found in the area,including 8 type I anomalies,4 type II anomalies,and 2 type III anomalies.Type I and II anomalies have good mineralization indications.According to the anomalous characteristics of ?T,15 concealed diabase dikes have been delineated,most of which are located at the intersection,branch or intersection of the structure.The distribution characteristics of NW,NE and nearly EW trending faults have been found out.NW trending faults are the main faults in the area.They are not only formed early,but also have a large scale and play a role in controlling rock,ore and ore.The results of electrical parameter measurement and geophysical survey on the known orebody show that the lead-zinc orebody occurs in the cross composite position with high charging rate,low resistivity and different tendency faults.Produced near the transition zone of high and low resistance,near the side of high resistance;Diabase is produced in the footwall of F2 fault,showing the characteristics of low or medium low resistance and high charging rate.Combined with the characteristics of metallogenic geology and geophysical anomaly of orebody,a geological-geophysical prospecting model is constructed.Combined with the prospecting model,the comprehensive comparison of the geophysical prospecting anomaly areas of each method is made,and the six prospecting target areas,such as Wuliping,Changpingzi and Dapingzi,are further selected.The good work results are obtained,which also provides guidance for the subsequent prospecting work of lead-zinc deposit. |
PDF Full Text Request