• 责任者：Hu Peiyuan (College of Earth Sciences ; Jilin University ; Changchun 130061 ; China) ; Li Cai
• 刊名：Acta Petrologica Sinica
• 出版年：2013
• 卷期：29(12)
• 关键词：蛇绿岩 ; ophiolite ; 花岗岩 ; granite ; 钠长石 ; albite ; 羌塘盆地 ; Qiangtang Basin
• 页码：p.4404-4414
• 图表：12 illus., 3 tables, 67 refs.
• 分类号：0801
• issnNo：ISSN1000-0569
• isbnNo：CN11-1922/P

     This paper reports new zircon U-Pb age and Hf-isotope, and whole-rock major and trace element data from albite granite body located in Heiji Mountain area of Longmu Co-Shuanghu-Lancang River suture zone, central Qiangtang, northern Tibetan Plateau. The albite granites intrude into Taoxinghu ophiolite. Combined with high Th/U ratios （0.41~1.06）, their zircons show no euhedral crystals and have clear oscillatory zones, indicating a magmatic origin. Zircon LA-ICP-MS dating for albite granite yields a weighted mean age of 351.21.9Ma, suggesting that the crystallization age of Heiji Mountain albite granite body is Early Carboniferous. These granites are characterized by high SiO2 and Na2O/K2O and belong to aluminous-peraluminous, calc-alkali and I-type granites. Their REE model is characterized by enrichment in light REE and positive Eu anomaly, and they are enrichment of Rb, Th, U, K, Pb, Zr and Hf, and negative anomalies of Nb, Ta, Ti. These features suggest that the albite granites were formed in island arc setting. Their zircons have positive εHf（t） values （＋11.56~＋14.46）, second stage Hf mode ages （tDM2=432~581Ma） which is older than zircon U-Pb ages, indicating they were genetated by partial melting of subducting oceanic crust. The determination of Heiji Mountain albite granites indicates that the subduction of Paleo-Tethys Ocean crust in central Qiangtang had initiated at Early Carboniferous.