| Hongshi gold deposit locates in the southeast of Shanshan county,it hosts in Kangur ductile shear belt,there are two ore-belts named L1 and L2,the main types of the wall-rock alterations are silicification,pyritization,sericitization,chloritization,carbonatization and so on. The type of ore is quartz vein network.According to the feature of Hongshi gold deposit,it was divided into two mineralization phases,dynamometamorphism hydrothermal phase and oxidizing phase.Then, dynamometamorphism hydrothermal phase can be divided into four mineralization stages: Pyrite-sericite-quartz stage is the early mineralization stage,Au-pyrite-Magnetite-quartz stage is the gold bioaccumulation stage,Au-polymetallic-pyrite-quartz stage is the further bioaccumulation stage,carbonate-quartz stage is the gold dilution stage.Finally,the surface of the gold deposit was oxidized and leached.Based on the field geo-investigation and synthetic study,the ore-bearing strata of Hongshi deposit is Gandun Group,it is clastic formation of turbidite deposit,the Au average abundance is 11.20×10-9,the mean value of variation coefficient is 1.33,that is extremely thenon-uniform unusual element.The emplacement age of Quartz-Diorite in north-east of the deposit is 275-248Ma,tally with the metallogenic period polymetallic sulfide stage(258±21Ma).The assemblage of metamorphic minerals are pyritization-sericitization,the metamorphy of Carboniferous showed the feature of low greenschist facies and dynamometamorphism;The main faults are east-west trending,the high intensity and low-temperature shear-brittle belt contain plenty of mylonite and phyllonite stride over the middle of Hongshi,brittle fault stack on the old structure later which made the field structure appearance more complex.Analyzing the geological facts syntheticly,Au accumulate in Gandun Group,it provided adequate material conditions;magmatism potentially heated the groundwater,activated the mineral between strata and ductile shear zone,even migrated,dynamometamorphism make Au activation under low greenschist facies.The gold belt was controlled by the ductile shear zone. Shear foliation is the passages for metallogenetic elements to metasomate and replace,the extensive space of ductile shear deformation belt or brittle deformation zone are advantaged metallogenetic space.The east-west trending faults controlled the distribution of the deposits, the intersection of east-west trending faults and north-west trending faults supplied the host space of the deposit.The samples of 20 line and 1080 section show that Hongshi gold deposit has its own characters,finally,ascertain zonation succession of the Hongshi gold deposit by various method is Bi-Mo-Hg-Zn-Pb-Ag-As-Cu-Sb-Au.Comparing with China typical gold deposit zonation succession,it was discovered that it has inversed zoning feature,thereby,set up its zoning evaluated and ore body superimposed patters to predict its depth concealed ore-body,it has ore-forming potential.
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