Geological Characteristics And Genesis Of Xixibao Manganese Deposit In Songtao Area Of Northeast Guizhou

The fault depression zone in northeast Guizhou is an important manganese ore metallogenic belt in Guizhou,and a set of complete"Black Rock series"is developed in the period of the new Proterozoic large pond,and the manganese ore is mainly deposited in the Black Rock system.Taking songtao xixibao manganese deposit as an example,this paper discusses the source and origin of the metallogenic materials of this type of manganese deposit through the research methods of the geological characteristics of the deposit,the geochemistry of the deposit and the fluid inclusion.The following research results are obtained:?1?The changes of elements Mn/Fe,MnO/Al₂O₃,Co/Zn,Ba/Sr,Y/Ho,La/Ce ratio and?Ce values all show the characteristics of hot water sediments,and in Co/Zn-?Cu+Ni+Co?diagrams,La-Ce relationship diagrams and La/Yb-REE diagrams,The projection points of ore samples all fall in the hot water sedimentary area,which reflects the strong influence of hot water on the enrichment and mineralization of manganese.?2?Element Al₂O₃/?Al₂O₃+Fe₂O₃?,Al/?Al+Fe+Mn?ratio and?Eu value change,?Na₂O+K₂O?-SiO₂ and La/Ce-Al₂O₃/?Al₂O₃+Fe₂O₃?diagrams,All indicate that the manganese-containing rock system is formed on the passive continental edge background.?3?The enrichment of elements V,U and Mo values,and the ratios and diagrams ofV/Cr,Ce/La,V/?V+Ni?,V/?V+Cr?,?U+V?/?U+V+Mo?reveal that manganese containing rocks are formed in hypoxic environments.?4?The temperature of the fluid inclusions in the ore of the fluid inclusions?on average 177°C?and salinity?average in 6.6%NaCleqv?and the characteristics of CH₄,CO₂and N₂ components show that the manganese ore mineralization process is affected by strong hot water action,and there is also the participation of deep gas.Therefore,the ancient passive continental margin is an ideal place for the enrichment of manganese ore,and hot water activities provide a rich source of material for it.