Genetic Mineralogy And Deep Prospects Of ZhaoDaoShan Glod Gold Deposit In Muping, East Shandong Province

ZhaoDaoShan gold district,the typical quartz vein type gold doposit in the Northeast of Shan dong province,located in the north of the Muping-Rushan ore-formingbelt,occurs in Mesozoic Kunyunshan monzonitic granite. Ore bodies are controlled by the Jinniushan tectonic zones of NNE striking faults. The regularity of the ore genesis and mineralization enrichment is studied by genetic mineralogy research of quartz and pyrite in this thesis. Base on the understanding,the prospective prognosis in depth and periphery of the auriferous quartz vein ore were proposed.Microthermometric data of fluid inclusion shows that ore-forming fluids is moderate to low temperature,moderate to low salinity,low density and CO₂,CH₄ and H₂S-rich.The trapping pressure is estimated at least to be 44.8 to 98.1MPa,with most of the trapping pressure ranging from 50 to 70MPa.the ore-forming depth ranges from 5.31 to 8.17km and centers around 6.0 to 7.0km.The morphological characteristic of pyrite is pentagonal,cube and their combination,the frequency of the combination of pentagonal and cube is the highest in the chief metallogenic stages.The compositions and thermoelectric characteristics studies show that the composition of pyrite is poor in S,but rich in As;the typical elements same as others in the eastern Shandong province are comprised by the trace element As,Co,Ni,Mo,Se,Au,Ag,Sb,Pb and Te;the pyrelectric coefficient is at range of -340³47μV·℃-1 and the proportion of P-type pyrite is 61 percent,it is characterized by wide dispersion of a value of the pyrite from the Zhaodaoshan gold deposit;the type of the electric conduct assemblage for the pyrite changes P>N→P>N→P>>N from stageâ… toâ…¤;the mineralization temperature is 150 to 340℃. Combined with some typomorphic informations on the crystallizing temperature of pyrite,the changes of thermoelectrical coefficient in depth,the distribution of pyrite type and the mean of thermoelectric coefficient,it is concluded that the genesis of Zhaodaoshan gold deposit belongs to the hydrothermal gold ore deposit of Middle-low temperature;the denudation rate is lower and the deeper parts of ore body haven't been exhumed until now,the higher region of the value of a p and P% often indicates the rich ore segment. It is characterized by lower explosive temperature and higher intension of the pyrite for the chief metallogenic stages,which is consistent with the Au-rich segments.The analytical result of helium and argon isotope show that the source of matallogenic material is mainly from low crust,and the mantle fluids were inwolved in the metallogenic process. According to the classification about the gold deposit,it is similar to the model of orogenic gold deposit.Based on the lithology of the wall rocks,the tectonic regularity,the character of buried ore and the typomorphic characteristics , three predicting target areas were proposed in depth and peripheral.They are distributed over line 8 to line 16,line 64 to line 68 and near the line 120,all of them have been verified by drilling hole in field.