The Relat-ionship Of Granite Characteristics And Its Minerlization Of Luanchuan District

Luanchuan ore-concentrated district is an important part of East Qinling molybdenum metallogenic belt,which has three super-large molybdenum polymetallic deposits and many large and medium-sized deposits.These deposits are closely related to granites,which are located in the granites or the contact zone of the granites and its wall rock.However,there are some difference between the grantes on minerliazation scale and combination of ore-forming elements.Based on research of granite petrography,petrology geochemistry and Sr,Nd,Pb,O,S isotope geochemistry,the article analyses granites genetic types,the sources of granites diagenesis and mineralization,the quantitative modeling of trace elements and the study of ore differences from the stratum,structure and granites characteristics aspects.The granites of this district belongs to I type with metaluminous-peraluminous and high potassium Calc-alkaline to alkaline rock series.Compared to Laojunshan batholith,ore-bearing granites undergone higher magma evolution,which are abundant in silica,potassium,alkaili and lack of magnesium,calcium.In terms of trace elements,the ore-bearing granites and laojunshan batholith presents a similar trend on REE patterns,showing a downward trend from left to right:LREE enrichment,HREE loss,with negative Eu anomaly;The two kind of granites show the enrichment of Rb?Th?U?K,strong enrichment of Pb and show the lack of Ba?Nb?Ta?Ce?P?Ti on chondrite-standardized spider diagrams,implying the Crust source.There are still some difference:the former one has lower gross REE and higher magma evolution;The granites are derived from the partial melting of lower Crust and the minerlization materials are derived from the magma by the analysis of Sr?Nd,?Pb?O?S isotope.The ore-bearing granites and laojunshan batholith are derived from Taihua Group metamorphous greywacke with a forty percent and fifty percent degree of partial melting.On terms of the differences in ore mineralization,the emplacement stratigraphy,tectonic settings and rock characteristics of the granites lead to different metallogenic scale;Caledonian metagabbro that outcrops in the northern part of the Shangfanggou mine lot result in the difference of combination of ore-forming elements that shangfanggou granite porphyry ore-forming elements are Mo and Fe.