Discussion On The Ore Genesis Of Jinshan Gold Deposit And The Three Demensions Prognosis, Northeast Of Jiangxi

Jinshan gold deposit was founded in the Dexing Cu-Pb-Zn-Au-Ag ore concentration area at 1980s,which is a super large gold deposit related to the Jinshan-Xijiang ductil shear zone, northeast of Jiangxi province.The tecnotic position of the deposit was on the Dexing bolck which is collaged by the collision of the Yangtze plate and Cathaysian plate,just located in the Jinshan-xijiang ductil shear zone,which is the sub-structural of the "ductil shear opholite complex zone,northeast of jiangxi".The ore genesis of Jinshan deposit has always been a focus during the geologist,and the three demension metallogenetic prognosis in the depth of jinshan deposit is a technical problem ungency need to be solved.Based on the previous research results,rely on the national scientific subject "exploration technique research and depth prospecting progonosis in Dexing-Yongping ore-centralization area,northeast of Jiangxi ",aming at the current problem,this paper focuses on discussing the ore-genesis and the Metallogenic Regularity of the deposit through traditioanl ore minerology research method and Mathematical Geology method.Achieved the depth location prediction of Jinshan gold deposit based on three demension geological model. The main achievements and innovation obtains through this research as follows:(5) The research of fluid inclusion from different depth samples show that:H₂O-NaCl two phase inclusions,CO₂-H₂O and pure CO₂ inclusions has been founded in the same mineral,the three type inclusions have a similar homogeneous temperature(241.8℃-270.4℃),however,the sanility and the CO₂ contents of these inclusions are in different value.The reason for this phenomenon may be the phase separation mechnism of H₂O-CO₂ fluid system,which formed the H₂O-NaCland pure CO₂ fulid inclusions.Phase separation was possibly one of the most important Au element depostitional mechanism.Quartz vein type fluid inclusion was tested contain a lot of organic components show that reducing gas plays an important role in the precipitation of the Au element;(6) The sulfur isotope value(δ³⁴S) of the quartz vein type ores is confined in 3.2‰-7.3‰,the average value is 5.37‰.δ³⁴ S value of the mylonite type ores variation range is -1.5‰-5.1‰, average value is4.18‰.the averageδ³⁴S value of Shuangqiaoshan group is 5.47‰.Two type(quartz vein type and mylonite type) of orebody and wall rock have the same sulfur source which come from the crust,which sharp contrast with the Tongchang porphyry copper deposit's sulfur feature(0.15‰-1.48‰,average value=0.15‰) indicates that Jinshan gold deposit and Tongchang copper deposit have a difference sulfur source.Theδ³⁴S value of Yangshan ore section from Jinshan deposit is -0.4‰,which smilar to the Tongchang sulfur Characteristics may indicates the influnces which the magma activity to the metallogenic of Jinshan deposit.(7) Achieved the 3D visualization of Jinshan ordbody for the first time.The surface model,structural alteration zone model have been eatablished.It also simulated the morpholoy of the main shear surface.These model would provide the basis for the depth location prediction of Jinshan gold deposit.The variogram of the gold grade shows that parameters of variogram could describe the changes of the spatial structure.Through the study of variogram points out that the lateral dissolution may be the dynamics mechanism of the Au element precipitation. The fractual study of gold grade of Jinshan gold deposit shows that the fractual structure of the ore grade could characterize the geological process on which when the ore formed underwent On the basis of the regularity of the fractual demcnsion of the drillhoels,point out that metallogenic potential is notability in thc deep of line 301to line 309 and line 321 to line 329.(8) Eatablised a set of method combination of 3D depth location prediction in old mines,and achieved the depth location prediction of Jinshan gold deposit based on three demension geological models,delineated four taget areas for verification,also analyze the shortages of this method.At last,this paper attempt the method innovation of depth prediction in mines,proposed a new method that three demensions Metallogcnic Prognosis based on information content-weight of evidence method,also give the technical process of this method.It is worth to further study on the new method.