• 责任者：He Mengying (Key Laboratory of Surficial Geochemistry ; Ministry of Education ; School of Earth Sciences and Engineering ; Nanjing University ; Nanjing 210093 ; China) ; Zheng Hongbo
• 刊名：Quaternary Sciences
• 出版年：2013
• 卷期：33(4)
• 关键词：物源分析 ; provenance analysis ; 铀—铅计时 ; U-Pb dating ; 现代沉积 ; recent deposit ; 长江 ; Yangtze River
• 页码：p.656-670
• 图表：12 illus., 1 table, 64 refs.
• 分类号：1400
• issnNo：ISSN1001-7410
• isbnNo：CN11-2708/P

     A total of 24 sand samples were collected in the mainstream and major tributaries of the Yangtze River drainage basin.The sample sites include the whole drainage,from the source ＂Tuotuohe＂ to the river mouth.Three samples were taken at the confluence of the mainstream and tributaries,avoiding potential contaminates.24 samples were dated by the LA-ICP-MS U-Pb technique and 10 samples were analyzed for Hf isotopes on the same spots of concordant grains.Our results show that most zircons are from igneous rocks,so the ages of these zircons could represent the time of their crystallization.The U-Pb age specturm define six age groups in mainstream of the Jinshajiang：2.4-2.6Ga,1.8-2.0Ga,700-1000Ma,400-550Ma,200-300Ma and 〈65Ma （Fig.7A-7D）,and two in the tributaries：700-900Ma and 100-300Ma（Fig.8A-8D）.There are four age groups in the Chuanjiang：2.4-2.6Ga,1.8-2.0Ga,700-1000Ma and 200-300Ma（Fig.7E-7G,Fig.8E-8F）.Among which,2.4-2.6Ga are enrichment in the Jialingjiang and Wujiang.Five age groups display in the mainstream of the Midstream：2.4-2.6Ga,1.8-2.0Ga,700-1000Ma,400-500Ma and 200-300Ma（Fig.7H-7K）,whereas 〈1Ga age population in the tributaries：700-900Ma,400-500Ma and 200-300Ma（Fig.8G-8I）.400-500Ma age range is the main group in the Midstream.The Downstream is a little similar with the Jinshajiang,and exist ca.1 % age younger than 65Ma,but 2.4-2.6Ga age group is minor（Fig.7L-7N）.According to the zircon U-Pb age,the Yangtze River can be divided into four segments,which is consistent with the geography division.Combined with the Hf isotope,it can be considered that zircons aged Mesozoic-Cenozoic were mainly from the Songpan-Garze terrane,and zircons dating Paleozoic were from Qinling orogenic belt.The Yangtze Craton,Cathaysia Block and Dabie orogenic belt are the main source of Archean-Proterozoic zircons.