Study On Geological Characteristics And Sedimentary Environment Of Xialei Manganese Deposit In Guangxi

Guangxi Daxin Xialei Devonian manganese deposit is my country's first super-large manganese deposit,and it is a typical"thunder type"manganese deposit.On the basis of previous studies,this paper uses the research ideas and methods of gas-liquid spouting sedimentary manganese deposits to carry out the field geological survey of the Xialei manganese mining area and the comprehensive analysis of the drilling data of the mining area.The genesis of the Pennian manganese deposits were discussed,and the following new understandings were put forward:(1)For the first time,it was discovered that the spouting sedimentary structures that may lead to the formation of manganese ore,such as brecciated manganese ore,vein-shaped manganese ore,etc.The secondary sorting,development and comprehensive study of the drilling data in the Xialei manganese mining area revealed that the brecciated and vein-shaped ores in the Xialei manganese mining area have unique spatial distribution patterns,concentrated in 5 areas,which may be caused by manganese gas liquids.Spouting orifice of spouting sedimentary mineralization.(2)Through the analysis of the thickness,ore body thickness,and grade distribution rules of the manganese-bearing rock series in the mining area,it is found that the ore body thickness,grade and the spatial distribution of the manganese-bearing rock series thickness are positively correlated.The direction of the long axis of the liquid jet overflow is the same.Based on this,three syn-sedimentary faults,namely SF₁,SF₂,and SF₃,were successfully restored in the lower-lei-tuhu graben basin of the Wuzhishan period in the Devonian period.(3)The mineral composition and microstructure structure of the ore in the mining area were studied,and it was found that a large number of manganese silicate minerals and sulfides developed in Xia Lei manganese ore,mainly including rhodonite,manganese-iron chrysotile,rhodolite,manganite,yellow Iron ore,magnetite,chalcopyrite,galena,sulphur-nickel-cobalt ore,etc.,which are difficult to explain in the traditional understanding of exogenous sedimentary mineralization of manganese ore.(4)The Xialei-Longbang sub-basin was divided,and the prototype of the Devonian Xialei-Tuhu graben?graben basin that controlled the Xalei manganese deposit was initially restored.Three syn-sedimentary faults developed in the basin,which resulted in the formation of five“three large and two small”vents,and provided a large amount of minerals to the basin.The hydrodynamic force in the basin is weak and the sedimentary environment is relatively reduced,which is suitable for large amounts of manganese minerals..(5)Using the analogy method,the Xialei manganese deposit and the Guizhou Datangpo gas-liquid spouting sedimentary manganese deposit were compared and studied.It is found that the two have a high degree of similarity in terms of mineralization background,ore-controlling structure,ancient spouting orifice group,ore structure and ore zoning,and only slightly in terms of mineralization age,ore-bearing strata,ore composition,etc.different.Therefore,the origin of the Xialei manganese deposit may be a gas-liquid spouting sedimentary manganese deposit.