Hf Isotopic Compositions of Zircons from 2.7 Ga Metasedimentary Rocks and Biotite-Plagioclase Gneiss in the Mengjiatun Formation Complex, Western Shandong Province

• 责任者：Du Lilin (Institute of Geology ; Chinese Academy of Geological Sciences ; Beijing 100037 ; China) ; Yang Chonghui
• 刊名：Acta Geologica Sinica
• 出版年：2010
• 卷期：84(7)
• 关键词：黑云母片麻岩 ; biotite gneiss ; 铪同位素 ; hafnium isotopes ; 变沉积岩 ; metasedimentary rocks ; 山东 ; Shandong Province
• 页码：p.991-1001
• 图表：5 illus., 1 table, 64 refs.
• 分类号：0802
• issnNo：ISSN0001-5717
• isbnNo：CN11-1951/P

Lu-Hf isotopic compositions of zircons separated from the garnet quartzite (M08), staurolite-bearing garnet-biotite-quartz schist (D242-Y2) of the Mengjiatun formation complex and biotite plagioclase gneiss (M03) of the TTG gneisses at Mengjiatun village, Xintai City, western Shandong Province, have been analyzed through the La-MC-ICP-MS method. All the rocks mentioned above were formed 2.7 Ga ago. Combining with the regional geology information, the authors deduce that the 2. 7 Ga magmatism is an important magmatic tectonothermal event in the western Shandong Province area, even in the North China Craton. Many zircons in the metasedimentary rocks show the tendency that the metamorphic overgrowing rims have lower ¹⁷⁶Lu/¹⁷⁷Hf but higher ¹⁷⁶Hf/¹⁷⁷Hf values than that of the magmatic cores, demonstrating the substantial influence of the metamorphic garnet on the Lu-Hf isotopic system of zircons.