Reasearch On The Ore-controlling Structure And Prospecting Prediction Of Bailezhai Copper Mine In Jinping County Of Yunnan

The copper ore in Bailezhai, Jinping county, Yunnan, as for geotectonics, is located in the contact zone of the southwestern margin of the yangtze platform and the southeastern margin of Tangula-Changdu-Lanping-Simao fold system. As for geography, it is located in the southwest side of the Ailao Mountains-Tengtiao River fault zone. It is a part of the northwest margin of the Tengtiao River polymetallic ore concentration area of the southern section of the Ailao Mountain polymetallic metallogenic belt. Affected by regional tectonic activities, the tectonic zone of Ailao Mountains has experienced many tectonic-magmatic activities. Thus, the deformation activity of the mining area is strong and fault structure is its main pattern of manifestation that controls output and distribution of ore body within the area.Based on comprehensive analysis of the geological background of regional mineralization and geological conditions of mineralization, this paper summed up fault structure of different levels and directions systematically, and summarized characteristics of structural ore-control of this mining area; in combination with comprehensive analysis of abnormal information such as geochemical exploration, prospecting target areas was circled. Some ideas obtained in this paper are as follows:(1) The copper body in the research area was stratiform-like and lento id which existed in the fault zone and the side fracture. Its output was controlled by multi-factors including stratum (T3g1), lithology (contact areas of limestone and sandy slate), tectonics (north-west and north-northwest fault), wall rock alteration (pyritization, silicification and carbonatation etc.) magmatic-hydrothermal activities etc. in which tectonics was a main factor of ore control.(2) In the research area, the north-west fault and the secondary north-northwest fault formed γ-type structural ore-control. Output and distribution of ore body within the area were controlled strictly by taking the north-west fault as ore-conducting structure and branch faults over it as ore-bearing structure.(3) Combined with the geometrical morphology of ore output, characteristics of ore-controlling faulted structure and ore mineral assemblages, and feature analysis of wall rock alteration, this paper considered that this ore deposit was a hydrothermal type copper deposit.(4) Based on geologic features and fault structure ore-control features of the ore deposit within the research area,2 prospecting target areas was circled in combination with analysis results of geophysical and geochemical data and other clues for prespecting.