Study On Geological Characteristics And Genesis Of The Pating Gold Mercury Deposit In Danzhai,Guizhou

The Paiting gold-mercury deposit is located in the northern of the Sandu-Danzhai polymetallic metallogenic belt.It is a representative part of a large low-temperature metallogenic region in south China.In the previous tailing survey,it was found that the Paiting gold-mercury deposit has high grade gold ores.However,there are few studies on the deposit of Sandu-Danzhai metallogenic belt,and scholars have different idea about it's metallogenic fluids,material sources,genesis of deposit and metallogenic model and so on.Therefore,this paper systematic collected and sorted out the related datas and carried out the detailed field geological survey.And through the petrographic study and the electron probe to analyze the occurrence state of gold,and divided the metallogenic period.And though the analysis of main,trace and rare earth elements,the sulfur isotopes,the C-O isotopes,the organic carbon isotope,the sources of metallogenetic materials and the metallogenetic fluids characteristics were studied,the genesis of the deposit were determined,the metallogenic model was established.The main results are followed:(1)Pyrite is divided into two phases(excluding the supergene):the sedimental-diagenetic pyrite is characterized by strawberry pyrite and cubic pyrite.The hydrothermal pyrite in the metallogenic stage is divided into pyrite in early metallogenic stage(Py?),pyrite in main metallogenic stage(Py?)and pyrite in late metallogenic stage(Py?).Most of the gold bearing mineral in the Paiting gold-mercury deposit is arsenopyrite,followed by arsenic pyrite in the main stage of mineralization.All the gold in the arsenopyrite is in the form of invisible solid solution(Au~+)and there is nanoscale native gold in arsenic pyrite,and it is probable that there is visible gold.The outer belt of annulus pyrite is rich in As and Au and poor in Fe and S.The core of annulus pyrite is rich in Fe and S and poor in As and Au.(2)The main sulfur of stibnite and mercury in the Paiting gold-mercury deposit comes from strata sulfur,the second comes from biological sulfur.The carbon in the metallogenic fluids is multi-source,which comes from the deep magma,the dissolution of carbonate rocks and the carbon provided by organic matter.The oxygen in metallogenic fluids mainly comes from surrounding rock.The characteristics of trace elements indicate that other major mineral elements,As,Ag and Pb mainly come from the deep mantle,Sb and Tl mainly comes from the crust.(3)There are mainly two metallogenic stages in the Paiting gold-mercury deposit:the first stage is magmatic-related hydrothermal mineralization,that is,gold enrichment and mineralization in this stage.The gold elements mainly come from the deep,the gold deposits(mineralization)formed while the deep magmatism carries Au,As,Fe and other metallogenic elements along the faults migration up and the in the gold deposits(mineralization)occurrence between the sedimentary sequences,stratification and tectonic space;the second stage is the hydrothermal of strata fluids transformation and mineralization,that is,mercury enrichment and mineralization in this stage.Due to the strata fluids(thermal fluid driving),occurring calcite precipitation,local antimony mineralization,and the formation of mercury.(4)In the early stage of the gold-mercury mine in Danzhai,mainly to mining for mercury.There is no comprehensive utilization of the common(companion)gold resources.Therefore,the residual gold in the abandoned mine adit has great resource potential and is worth to further work.