Studies On Geological Characteristics And Ore-controlling Factors Of Silihe Stibium(gold) Deposits In Taojing, Hunan Province

Silihe stibium(gold) mining area has been extract for one hundred years,which is located at Taojiang county of Yiyang city in Hunan province.The strata exposed in the mining site are the Wuqiangxi Formation of Upper Proterozoic Banxi Group.The Sb-Au ores mainly distributes between the first and second sub-strata at the bottom of the middle formation.On the basis of analyzing the ore-forming geological backgrounds of Silihe mining area,in combination with the key-knowledges on petrology,tectonics,ore mineralogy,trace elements,deposits geochemistry,and so on,the author has done deeply researches on the ore-forming conditions,geological and geochemical features,causes of the Sb-Au deposits,ore-controlling factors and laws of mineralization. The main achievements are as follows:1.According to the systematic analyses on the tectonic evolutions in this region,the author believes that there exsited three big tectonic movements,including Wuling,Xuefeng and Caledonian ones,which made the structures spreading along EW,NE and NNE trending,and which resulted in the advantages for mineralizing in this area.2.Mineralization is mainly controlled by two factors-mesomere ledge horizons and ruptures of the Wuqiangxi Formation of Upper Proterozoic Banxi Group,and Magmation is highly related with ore-forming as well.The ore-veins in this area are mainly controlled by structures(ore-containing fault along EW trending,gently inclined interlayer fracture zone).3.From the obvious similarities of trace element contents among samples,which means resources of mineralization can be extracted directly from stratums and dikes of granite porphyry.4.By means of studies on the vapor-liquid contents of the inclusions, together with temperatures of the inclusions,which shows that the type of the mineralizing liquids is a mixed solution of lava and hot water of deep sources which belongs to the medium-low temperature and low salinity Ca²⁺—Na⁺—K⁺—F^-—Cl^-—SO₄^2-.5.According to the aboves,the author has established a new metallogenic model,and pointed out that the genetic types of Silihe Sb-Au deposits are polygenetic compound ones,which are multi-factors controlled,multi-resources and multi-stages mineralized.