LA-ICP-MS Zircon U-Pb Ages and Implications for Tectonic Setting of the Mangling Granitoid Plutons in Qinling Orogen Belt

详细信息   

• 责任者：Qin Haipeng (Institute of Geology Chinese Academy of Geological Sciences ; Beijing 100037 ; China) ; Wu Cailai
• 刊名：Geological Review
• 出版年：2012
• 卷期：58(4)
• 关键词：花岗岩 ; granite ; 铀—铅计时 ; U-Pb dating ; 秦岭 ; Qinling Mountains
• 页码：p.783-793
• 图表：illus., 2 tables, 47 refs.
• 分类号：0801
• issnNo：ISSN0371-5736
• isbnNo：CN11-1952/P

摘要

The Mangling granite is located on the north side of the Shannan--Danfeng foult, eastern sector of the north Qinling Orogen. The granite is in North-West-West streeh and in agreement with structural lineament. The paper reports the results of Zircon LA-ICP-MS U-Pb age and geochemical data. The results show that the Mangling granite includs two granite emplacements. Early Monzogranite whose ages ranging from 158.4 ± 1.8Ma to 160.5 ± 1.3 Ma belongs to Late Jurassic Early Cretaceous period and the late alkali granite has an age of 124.1 ± 2.0 Ma belonging to Middle Cretaceous. In addition, sample 09CL264 give inherited core age of 1883 ± 36Ma and 1860 ± 35 Ma belonging to proterozoie and may represent its protolith age. In geochemistry, monzogranite with the characteristics of high SiO₂, K₂O± Na₂O , K₂O/Na₂O〉 1 and high Sr low Yb, Y. The alkali granite has the characteristic of high SiO₂, K₂O ＋ Na₂O, K₂O/Na₂O〈 1 and low Sr low Yb, Y. The ε_Hf（t） values are from -9.4 to -3.1 which is consistent with previous study on ε_Nd （t）. In conclusion, the Mangling granite has character of multi-source and the main is proterozoic material in lower crust.