Genesis And Metallogenic Model Of The Nazhizhi Lead-zinc Deposit In Wuzhishan Area, Puding, Guizhou

Wuzhishan lead-zinc deposit cluster area is located in south-western of the Yangtze landmass,the western margin of guiyang complex tectonic deformation zone and southwestern adjacent of Weining north—west tectonic deformation zone.Adjacent Ziyun—Yadu and Puding—Zhengyuan fault on regional.The Nayongzhi Lead-Zinc deposit occurs in the southeastern limb of Wuzhishan anticline.The orebodies are mainly hosted in Qingxuedong Formation dolomite of the lower series Cambrian.In space,Ore bodies has three layers of zonal distribution characteristics,two types ore output forms are layered,stratified and steep vein.Using ICP-MS to analyze the trace and rare earth elements of ore,mineralized dolomite,surrounding rock,fault breccia,fault gouge,hanging wall and footwall of surrounding rock.Combined with the geology feature of ore deposit and ore sulfide sulfur,lead isotope research study,acquiring the following points:(1)Through the study of strata,lithology,structure and the mining area ancient geographical environment and the relationship between mineralization,lead-zinc mine output by structure,lithology,ancient sedimentary environment of multiple factors control,fault is the main ore-controlling factors,lithologic ore-controlling is better than that of Strata.Regional thrust fault F7 control ore deposit distribution and the lateral dispersion of interlayer faults control the output of the ore bodies.The lithology combination that upper argillaceous rock or shale and lower carbonate rock is favourable metallogenic;Limitation-semi limitation carbonatite phase platform environment is favourable metallogenic.(2)The distribution patterns of rare earth elements shows that the ore and surrounding rock is homologous,partial metallogenic material was from the surrounding rock.Contrasting research the spider diagram of trace element found that the enrichment of metallogenic elements was closely related to fault.Pro basic elements of V,Cr,Co,Ni,Cu from dolomite,mineralization dolomite to ore,presenting an increases change trend.Combining with the regional,these elements abundance value is higher in the Niutitang formation of lower Cambrian strata.So that metallogenic materials may be associated with the formation.Ore,fault breccia and surrounding rock,the element of U and Th enrichment significantly,may be has closely relationship with the regional high radioactive background.(3)The sulfur isotope shows that sulfur was derived from the marine sulfate thermochemical reduction of Sinian system and Cambrian strata.Lead isotopic composition is similar to dolomite lead isotopic composition of the Sinian system strata and has the feature of shell source.On the 206pb/204pb-207pb/204pb Lead isotopic diagram found that all fall into the line of average crustal tectonic evolution and with basement strata overlap,show that metal metallogenic material has the characteristics of multiple sources.(4)Contrasting this deposit with the nortnwest of guizhou Lead-Zinc deposit and typical(?)MVT Lead-Zinc deposit from geological background,main geological characteristics,sulfur and lead isotope composition.Nayongzhi Lead-Zinc deposit belongs to the typical MVT Lead-Zinc deposit.(5)Comprehensive Characteristics of the Geological,ore-controlling factors,paleogeographic environment and the source of metallogenic material studying can be summed up the metallogenic model of Nayongzhi deposit as "sedimentary-hydrothermal transformation enrichment".