Old Mining Area The Eastern Part Of Old Mining Field Information Metallogenic Prediction

This paper thesis was selected on the basis of scientific research projects sponsored by the Yunnan Provincial Government, named as the "Geological prospecting research over the east section of the Laochang mineralization field in Gejiu ore district, Yunnan", and "the Geology and geophysical prospecting in the Doushijie section of the Laochnag mineralization field of Gejiu ore district, Yunnan". The major practical workings completed for the research purpose of this paper are as follows: 40km2 geological survey and structural geochemistry survey and relevant chemical analysis over the Doushijie section in the east Laochang mineralization field of Gejiu ore district, Yunnan ; .Geophysical comprehensive study over the Doushijie mineralization section. Major study conclusions and results have been summarized as follows on the basis of combination of geological, geochemistry and geophysical study over the target area.1.In the study area, the major ore-forming elements display a concentrating tendency of being high in the west and low in the east and weakening towards southeast section with simpler elements association. The concentration centers was controlled by the NE-striking faults, and the major ore-forming elements anomalies extend in NE direction. The most associated elements concentrations are the Pb, Zn and Ag, with the Cu and Sn coming next to it.2.From the elements statistical analysis, it is concluded that the ore-forming elements were enriched in the study area, there is a remarkable difference in the elements contents, and there is a uneven distribution of ore-forming elements in the study.3. The low resistance anomalies show a superimposing features in different elevations, i.e. the location of anomalies remains un-changed in different elevation while the scope and scale of anomalies change in different elevation.4. The favorable mineralization zone should be located in south and north sections of the study area, and the most favorable targeting area is in the south section of the study area with larger anomalies. The low resistance anomalies which located in the elevations of 2100m and 1950m a.b.s were probably caused by the oxidized mineralization while the low resistance in 1750m levels is probably caused by the mineralization of skarn type.5. Three prospecting targets named as LCD-1^ LCD-2 and LCD-3 were outlined in the east section of the Laochang ore field and two targets named as DSJ-1 and DSJ-2 were outlined in the Doushijie section on the basis of combination of geological data and structural geochemical signature and geophysical anomalies.