class=MsoNormal><SPAN style="FONT-SIZE: 14pt" lang=EN-US>Zircon SHRIMP U-Pb Dating for Garnet-Rich Granite Veins in High-Pressure Granulites from the Namche Barwa Complex，Eastern Syntaxis of the Himalayas，and The Relationship with Exhumation

• 责任者：Qi Xuexiang (Key Laboratory for Continental Dynamics of the Ministry of Land and Resources ; Institute of Geology ; Chinese Academy of Geological Sciences ; Beijing100037 ; China) ; Li Huaqi
• 刊名：Acta Petrologica Sinica
• 出版年：2010
• 卷期：26(3)
• 关键词：麻粒岩 ; granulite ; 花岗岩 ; granite ; 铀—铅计时 ; U-Pb dating
• 页码：p.975-984
• 图表：6 illus., 2 tables, 25 refs.
• 分类号：0803, 0801, 1300
• issnNo：ISSN1000-0569
• isbnNo：CN11-1922/P

class=MsoNormal><SPAN style="FONT-SIZE: 14pt" lang=EN-US>The major and trace element data of the garnet-rich granite in the retrogressive granulite show that:1) they are high potassium，aluminum-rich；2) they are strongly enriched in LREE with high fractional degree，depleted in HREE，and enriched in LILE and RHE relative to primordial mantle；3) they have substantial negative Eu anomalies，and Rb/Sr>1.4．The magmatic initial temperature are ranging from 792℃ to 801℃ estimated by the major data and Zr contents for garnet-rich granite．The zircon SHRIMP U-Pb dating show that:1) the ages for the inherited cores are ranging from 519 Ma to 525 Ma，exhibit the Namche Barwa complex rocks had been lnfluenced in the pan-African movement；2) the latest growth rim of zircon grains have three stage ages of 39～44 Ma, 24～25 Ma and 7.3 Ma．