• 责任者：Wang Ping (School of Geography Science ; Nanjing Normal University ; Nanjing 210023 ; China) ; Zheng Hongbo
• 刊名：Quaternary Sciences
• 出版年：2013
• 卷期：33(4)
• 关键词：河流袭夺 ; stream capture ; 长江 ; Yangtze River
• 页码：p.631-644
• 图表：10 illus., 40 refs.
• 分类号：1400
• issnNo：ISSN1001-7410
• isbnNo：CN11-2708/P

     The Yangtze,the longest river in Asia,was hypothesized to be assembled through a series of Cenozoic capture events,such as the reversal of middle Yangtze River and the capture of upper Yangtze River,but the history remains largely unknown.Here,we present new geomorphic observations in the structural context of the eastern Sichuan basin,namely the eastern Sichuan fold belt,and identify an important drainage divide along the ＂midline＂ of this arc-shape fold belt.Based on longitudinal profile analysis,we find that the river capture events more likely occurred in the syncline valleys of low-relief landscape.Our results yield a new perspective on middle Yangtze River reversal,and we propose that the ＂midline＂ drainage divide,rather than the Three Gorges,was the starting site of middle Yangtze River reversal.In this manner,the reversal could have been accomplished by a sequence of river reversal over range-parallel segments in syncline valleys with less impact on the pre-existing drainage system in eastern Sichuan basin.Moreover,the Cretaceous-Cenozoic sedimentary records are investigated in western Jianghan basin,east of the Three Gorges,in order to provide timing constraint for middle Yangtze River reversal.The result indicates that the initial capture and reversal might start in Middle Eocene when the basin was filled by eastward-flowing,upward-coarsening braided river sequence of Cheyanghe Formation.The through-going Yangtze River might have been formed during Miocene time,accompanied by incision of the Huangling Granite and deposition of the Yangtze Gravels.