晚第四纪构造与气候控制下的金沙江支流巴楚河阶地序列  

Research on terrace sequence and sedimentary age characteristics of the Bachu River in the southeastern Tibetan Plateau

作　　者：刘妮娜[1,2] 田开飞 刘博 温凯 Liu Nina;Tian Kaifei;Liu Bo;Wen Kai(Chang'an University,Key Laboratory of Western Mineral Resources and Geological Engineering,Chang'an University,Xi'an 710054;College of Geology Engineering and Geomatics,Xi'an 710054;Anhui Transport Consulting and Design Institute Co.,LTD.,Hefei 230000)

机构地区：[1]长安大学西部矿产资源与地质工程教育部重点实验室,西安710054 [2]长安大学地质工程与测绘学院,西安710054 [3]安徽省交通规划设计研究总院股份有限公司,合肥230000

出　　处：《地质科学》2024年第1期224-234,共11页Chinese Journal of Geology(Scientia Geologica Sinica)

基　　金：中国地震局巴塘1∶1万城市活断层勘察项目(编号:5133202019000148)资助。

摘　　要：河流阶地的形成过程研究是理解地区气候变化、构造隆升过程的重要手段。巴楚河地处青藏高原东南缘,隶属于金沙江支流水系,两岸阶地发育。因其独特的地理位置,为第四纪以来青藏高原的隆升研究提供了天然场地条件,对该地区金沙江水系的形成演化过程的研究也具有重要补充作用。野外勘查发现,巴楚河发育有四级阶地。对阶地堆积物进行宇宙成因核素测年和光释光测年,得到T1~T4阶地形成时代分别为1.7±0.1 ka、2.3±0.21 ka、4.5±0.5 ka和62.3±2 ka。T4阶地的形成主要为构造活动因素影响,T1~T3阶地的形成和阶地沉积物的堆积主要与气候有关。通过对阶地的拔河高度和形成时代的分析得巴楚河阶地下切速率由慢到快再平稳。研究结果对巴塘地区气候变化及构造运动历史的研究提供重要依据,促进了该地区金沙江水系形成演化的研究,与前人对青藏高原全新世以来隆升过程的研究相互呼应。The study on river terraces is an important method to understand the process of regional climate change and tectonic uplift.The Batang section of the Bachu River is located in the southeastern Tibetan Plateau,which belongs to the tributary river system of the Jinsha River and has terraces on both sides.Because of its unique geographical location,it provides a natural place to study the uplift of the Tibetan Plateau since the Quaternary,and it plays an important role in the inversion of the formation and evolution of the Jinsha River system in this area.Field investigation showed that there were four terraces in the Batang area,which are T1~T4 terraces.According to cosmogenic radionuclide dating and optically stimulated luminescence dating of the terrace deposits,the ages of terrace formation from T1 to T4 are 1.7±0.1 ka,2.3±0.21 ka,4.5±0.5 ka and 62.3±2 ka,respectively.The T4 terrace was mainly controlled by tectonics,the formation of the terrace T1~T3 and the accumulation of terrace sediments mainly related to climate change.The results provide the reference for the study of climate change and tectonic movement in the Batang area,support the study of the formation and evolution of the Jinsha River system in this area,and promote the study of the uplift process of the Tibetan Plateau since the Holocene.

关 键 词：河流阶地 沉积年代 巴楚河 青藏高原 

分 类 号：P534.63[天文地球—第四纪地质学] P931.1[天文地球—古生物学与地层学]