Multiple-stage W mineralization in the Guanfang W deposit,southeastern Yunnan Province,China:Insights from scheelite in-situ trace elemental and Sr isotopic analyses  

作　　者：Bin Sun Yi Liu Zhigang Kong Xuelong Liu Xiaojun Jiang Chao Li Wenchang Li 

机构地区：[1]Faculty of Land Resources Engineering,Kunming University of Science and Technology,No.727 South Jingming Road,Chenggong District,Kunming City 650093,Yunnan Province,China [2]Institute of Mineral Resources,Chinese Academy of Geological Sciences,No.26 Baiwanzhuang Street,Xicheng District,Beijing 100037,China

出　　处：《Acta Geochimica》2025年第1期112-127,共16页地球化学学报(英文)

基　　金：suppor ted by Yunnan Major Scientific and Technological Projects(Grant No.202202AG050006);the Personnel Training Project of Kunming University of Science and Technology(Grant No.KKZ3202221022)。

摘　　要：The Guanfang large-scale W deposit is located in the W polymetallic ore concentration area of Bozhushan in southeastern Yunnan,China.Despite extensive research,the fluid evolution process of the deposit remains ambiguous,leading to controversy regarding its genesis.This study conducted a detailed field geological survey,with systematic sampling of the KT6 orebody,to delineate mineralization stages.Fine mineralogy work,including the use of CL images of scheelite,in-situ LA-ICP-MS trace elements,and Sr isotopes,was carried out on diff erent generations of scheelite formed in various stages.The findings identified the evolution of fluids in the mineralization process,shedding light on the genesis of the deposit.The study revealed four mineralization stages at the Guanfang W deposit:prograde skarn stage,retrograde skarn stage,quartz-sulfide stage,and carbonate-fluorite stage.Diff erent generations of scheelite(Sch I,Sch II,Sch III)were observed in the first three stages,displaying distinct chondrite-normalized REE patterns.The REE of Sch I mainly substituted into the Ca site by REE^(3+)+□_(Ca),and there may be a similar substitution of Nb for REE,whereas it is not the main substitution method.The REE of Sch II mainly enter the scheelite lattice in the form of REE 3++Na+,and there may be a substitution of Nb for REE isomorphism.In the early stage,The REE of Sch III was mainly replaced by Nb for REE isomorphism,while in the later stage,the replacement mode of REE^(3+)+□_(Ca)coexisted with it.The Mo content in scheelite,along with the corresponding Eu anomalies in both scheelite and garnet,collectively imply that the ore-forming fluids during various mineralization stages were predominantly oxidizing,with only slight reducibility observed in Sch II.The in-situ Sr isotope ratios of scheelite concentrates ranged from 0.7093 to 0.7153,resembling those of the Bozhushan granite,indicating a relationship between W mineralization and granite.In addition,the Y/Ho ratios of scheelite from various mineralization stages exhibi

关 键 词：Guanfang W deposit Trace elements of scheelite In-situ Sr isotopes Southeast Yunnan 

分 类 号：P618.67[天文地球—矿床学]