Geochemistry of Granitoid Rocks of Shedong W-Mo Deposit District in Cangwu County
详细信息
- 责任者：Chen Maohong (MLR Key Laboratory of Metallogeny and Mineral Assessment ; Institute of Mineral Resources ; Chinese Academy of Geological Sciences ; Beijing 100037 ; China) ; Huang Zhizhong
- 刊名：Acta Petrologica Sinica
- 出版年：2012
- 卷期：28(1)
- 关键词：钨矿 ; tungsten ores ; 钼矿 ; molybdenum ores ; 花岗岩类 ; granitoid ; 岩石地球化学 ; lithogeochemistry ; 广西 ; Guangxi Province
- 页码：p.199-212
- 图表：14 illus., 1 table, 54 refs.
- 分类号：1001
- issnNo：ISSN1000-0569
- isbnNo：CN11-1922/P
摘要
The Shedong tungsten and molybdenum deposit in Cangwu County,Guangxi is a quartz-skarn type deposit related to granitoids.Major granitoids are comprised of Caledonian granodiorite,granodiorite-porphyry and Late Yanshanian granite porphyry in mineral district.Caledonian granodiorite and granodiorite-porphyry dominantly exhibit low Si,K,high Na,Al and basic components, thus can be classified to the normal calc-alkaline granite with strongly peraluminous.The rocks are characterized by low REE contents, high LREE/HREE ratios,weakly Eu depletion(δEu=0.62～0.70),depletion of Ti,Nb,Ta,enrichment of Th,U,Pb,Zr,Hf, low Rb/Sr ratio(0.78),obviously enrichment of W,Mo,Cu.Geochemical evidences indicate that early Caledonian granodiorite (-porphyry)are I-type granite,and formed in compression tectonic setting of early collision stage in intra-continent orogenic belt,and associated with W,Mo,Cu mineralization.Late Yanshanian granite porphyry dominantly exhibit high Si,K,low Na,Ca and basic contents,can be defined as the high-moderate potassium calc-alkaline granite with strong peraluminous.The rock is characterized by relative high REE contents,low LREE/HREE ratios,strong Eu depletion(δEu=0.03～0.06),depletion of Ti,Ba,K,Eu,more enrichment of Th,U,Sm,Dy,Y,Ho,Yb,Lu,high Rb/Sr ratio(7.56),clearly enrichment of Sn,Bi,thus it is assigned to Late Yanshanian S-type granite evolved well,and formed in intraplate extension tectonic setting of post-collision,and is related to Sn,Au mineralization.