HAN Yu-jie1, 2, TANG Hong-feng1, GAN lin1, 2
(1. Laboratory for Study of the Earth’s Interior and Geofluids, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550002, China;
2. Graduate University of the Chinese Academy of Sciences, Beijing 100049, China)
Abstract: Laoyaquan granitic pluton is the largest pluton containing tin deposit in the Beilekuduk tin metallogenic belt. It is mainly composed of biotite alkali-feldspar granites. LA-ICP-MS U-Pb dating for zircons from two samples yielded the 206Pb/238U ages of 301±2 Ma (2σ, MSWD=1.03) and 300±5 Ma (2σ, MSWD=5.90), suggesting that the emplacement of the pluton occurred at the end of Late Carboniferous. The Laoyaquan alkali-feldspar granite is enriched in silica, alkalis, REE, Rb, K, Th, U, Nd, Hf and depleted in Ba, Sr, P, and Ti, with a strong Eu negative anomaly, showing the features of A-type granites. Both the geochemical characteristics and the zircon U-Pb ages indicate that the formation of the pluton is related to the post-collision and the magmatic activity during Late Carboniferous in northern Xinjiang.
Key words: zircon; U-Pb dating; Laoyaquan; A-type granite; East Junggar; Xinjiang
E-mail: 64881523@qq.com
ACTA MINERALOGICA SINICA Vol. 32, No. 2, 2012, Page 193-199
