江汉盆地河流碎屑锆石U-Pb年龄特征及其对物源研究的启示

江汉盆地位于扬子板块北部,是长江演化研究的关键地区.锆石是河流沉积物中常见的副矿物,其U-Pb年龄谱对比被广泛用于物源示踪研究,但在江汉盆地还未系统研究.本文利用激光剥蚀电感耦合等离子质谱(LA-ICP-MS)分别对江汉盆地12条流入河流进行了922颗碎屑锆石U-Pb年龄分析,结合多维判别图(MDS)和已报道的河流碎屑...

Detrital Zircon U-Pb Age Characteristics of Main Rivers around Jianghan Basin and Implications of Provenance Tracing

Jianghan Basin, located in the north of the Yangtze Plate, is a key area for the study of the evolution of the Yangtze River. Zircon is a common accessory mineral in fluvial sediments, and its U-Pb age spectrum has been widely used in provenance tracing studies. However, it has not been systematically studied in Jianghan Basin. In this study, the U-Pb ages of 922 detrital zircons from 12 inflow rivers in the Jianghan Basin were analyzed using laser denudation inductively coupled plasma mass spectrometry (LA-ICP-MS). A multidimensional discriminant map (MDS) combined with the reported U-Pb ages of detrital zircons from rivers was employed to assess the U-Pb ages of detrital zircons from 12 inflow rivers. Further, the U-Pb age variation of detrital zircons from the main inflow rivers in Jianghan Basin was discussed herein. The U-Pb peak age composition of detrital zircons from the Yangtze River, Juzhang River, and Qingjiang River is different. The U-Pb age of detrital zircons in the Yangtze River and Hanjiang River, the two rivers with the largest sediment transport capacity in the Jianghan Basin, are different. The U-Pb age composition of detrital zircons in the Dabie Mountains is different from that of Hanjiang River and the Yangtze River. The U-Pb age composition of detrital zircons from the Mufu Mountains are different from the Yangtze River and the Xiangjiang River. The U-Pb age composition of detrital zircons from Qingjiang, Lishui and Yuanjiang rivers in the Wuling Mountains are different from Xiangjiang and Zijiang rivers. These differences reflect the influence of regional provenance on the sedimentary material composition of these streams. Therefore, the U-Pb ages of detrital zircons from the surrounding rivers of the Jianghan Basin have a good application prospect in the study of basin-mountain coupling and river evolution in the Jianghan Basin.