Research On Geological Characteristics And Metallogenic Conditions Of Qiaoergou Lead-Zinc Ore In Sichuan

Qiaoergou lead-zinc deposit is located in Ebian County of Sichuan Province, whose tectonic background is situated in the western margin of Yangtze terrane and the eastern margin of the north section of Kangdian axis. It belongs to Hongya ~ Ebian ~ Mabian ~ Leibo sub belts of mineralization, which is a significant region having large and medium-sized lead-zinc deposits. With detailed field geological survey, microscopic identification of plates and slices, and analyzing and testing major, trace, and rare earth elements, the geological characteristics and mineralization conditions of the lead-zinc deposit are analyzed detailedly, the metallogenic model is deduced and the exploration marks are summarized.Sinian Dengying and Cambrian Maidiping are the major emergence stratums, dolomite of Dengying formation is the main ore-host rock, and the distribution, shape and occurrence of the lead-zinc orebody are controlled by Houshan fault. The 1th # ore body having been found has an abrupt contact with the wall rock, the boundary is distinct, and the length of the orebody is about 1250 m, the occurrence is 281~330°?59~81°, the thickness is 0.65~1.1m.Ore minerals mainly include sphalerite, galena, pyrite, and gangue minerals mainly include dolomite, calcite, quartz. Ore texture mainly has the idiomorphic, hypidiomorphic and xenomorphic, metasomatic relict, poikilitic, filling, and corrugated texture. Ore structure mainly has the massive, brecciated, vein, spotted structure. The wall rock alterations mainly include siliconization, dolomitization, pyritization.The standardized distribution curve of trace elements and rare earth elements shows ore-forming material sources include wall rock and others. After comparing ore trace elements with upper mantle, Clark values, Emeishan basalt, the results indicate that ore-forming materials come from not only the wall rock but also upper mantle.The metallogenic geological conditions mainly include fault structure, stratum and lithology, and fault structure is the most important one. Exploration marks mainly include structure, wall rock alteration, geoche mical anomaly, old mining relics and gossan. In summary, the genetic type of this deposit is hypabyssal epithermal type with the characteristic of earth's crust and mantle, which is controlled by fault structure, and the metallogenic model of the ore deposit is deduced.