Geological Characteristics And Genesis Of The Keketale Lead-Deposit,Xin Jiang

Keketale deposit is a large deposit,located on the Altai metallogenic belt.Paper in full collection finishing related geological information,and predecessors research,and system description on the basis of geological features,and discusses in detail the structure of rocks and minerals under the microscope description;and analysed the trace element geochemistry of surrounding rock and the rare earth element geochemistry of sphalerite;and discussed the genesis of minerals such as pyrite and sphalerite,for keketale deposit of causes research provides has new of information,and comparison with similar deposits into deposit types.Keketale deposits exist Kangbutiebao group of early Devonian upper group lithologic,located in maizi basin to the South East the transition ends North of reverse wing.Controlled by the formation of ore bodies,is stratified,layered,lens-shaped output.Ore are mainly composed by sulphides,such as pyrite,sphalerite,Galena,and pyrrhotite.Ore impregnated structure,band structure,separation of solid solution structure,explain the residual structure show through multiple stages of a volcano-sedimentary metallogenic characteristics,and cataclastic structures,the crumpled structure,chrome(Corona)structure structure,displays the deposits were later superimposition of metamorphism and tectonic stress.Ore-near-rock trace element geochemical characteristics of variable rhyolitic tuff shows that enriched Ba,U,Nd,Sm and other large-ion lithophile elements,while losses such as Nb,P,Ti Sr and ather High field strength elements.Sphalerite and wall rocks(variable rhyolitic tuffs)with similar geochemical characteristics of rare earth elements,are relatively rich in light rare earth elements(LREE),poverty of heavy rare earth elements(HREE),and has a negative Eu anomalies,and Ce is no exception,that showing mineralization associated with volcanic activity.Sulfur isotope values in the deposits-20.6 thousand ~5.1 ‰,and focus on within-15 ‰ ~-6 ‰ to indicate that it comes from the bacterial reduction of.Lead isotope study indicates it is the source of data,not only from the Earth's mantle,from the orogenic belt and the upper crust.Ga/In value for 0.013~0.047 of sphalerite,much less than 1,which formed under the influence of volcanic hydrothermal;and value of pyrite in the S/Fe value for 0.96~1.11,Co/Ni is 0.49~3.15,both characteristics of sedimentary origin and characteristics of volcanic hydrothermal origin,which experienced a volcanic exhalative mineralization processes.Comprehensive analysis of keketale Pb-Zn deposit,was produced in the active zone of early Devonian continental margin volcanic exhalative-sedimentary formation of the volcanic cedimeng-hosted massive sulfide deposits.