Zircon U-Pb Age and Nd-Sr-Pb Isotopic Characteristics of Dayang-Juzhou Granite in fix = st1 ns = "urn:schemas-microsoft-com:office:smarttags" />Longyan , Fujian
详细信息
- 责任者：Zhang Chengshuai (Faculty of Sciences and Mineral Resources ; China University of Geosciences ; Beijing 1 00083 ; China) ; Su Huimin
- 刊名：Acta Petrologica Sinica
- 出版年：2012
- 卷期：28(1)
- 关键词：花岗岩 ; granite ; 铀—铅计时 ; U-Pb dating ; 福建 ; Fujian Province
- 页码：p.225-242
- 图表：12 illus., 6 tables, 70 refs.
- 分类号：0801
- issnNo：ISSN1000-0569
- isbnNo：CN11-1922/P
摘要
Makeng Fe deposit is a large strata-bound skarn-type magnetite deposit.Juzhou-Dayang granite exposed on either side of Makeng deposit,and had genetic relationship to ore bodies.The SHRIMP ziron U-Pb age of Dayang granite is 1 32.6±1.3 Ma,MSWD =1.3;The LA-ICP-MS ziron U-Pb age of Juzhou granite is 1 29.6±0.8 Ma,MSWD=2.3,indicating that they formed in Early Cretaceous,which identified with the time when Makeng deposit(1 30～1 33 Ma,Re-Os age)were formed.Juzhou-Dayang granite is regarded as the weakly peraluminous-metaluminous granite,which is characterized by high silicon,enrichment of alkali,low calcium and magnesium,and high differentiation index.The rocks have high and remarkably varying REE,and their distribution patterns show LREE enrichment with gentle right oblique deviation,and a"V"model characterized by significant negative Eu anomaly;The trace elements compositions are strongly enriched in Rb,U,Th and La and considerably depleted in Ba,Sr,P and Ti;(87 Sr/86 Sr) ⅰ= 0.70878～0.71 349,ε Nd (t)=-7.2～-8.6,f Sm/Nd =-0.27～0.1 6,t 2D M =1 51 1～1 637 Ma,(206 Pb/204 Pb) i =1 8.588～1 8.955, (207Pb/204Pb) i =1 5.660～1 5.682,(208 Pb/204 Pb) i =38.935～39.1 68,μ=9.54～9.59,ω=36.77～38.1 3.The petrogeochemistry and isotopic characteristics of Dayang-Juzhou granite show that it is regarded as the crust-derived type granite,and experiences high differentiated evolution.The lithospheric thinning in relation to paleo-Pacific plate is a likely responsible mechanism for their formation. The magma sources of the Dayang-Juzhou granite mainly derived from Proterozoic crustal materials,but also involved some portions of EMII component,which reduced crustal residence age of the granite.