雅鲁藏布江流域古堰塞湖群的发育及其地质意义初探  

A preliminary study on the development of dammed paleolakes in the Yarlung Tsangpo River basin,southeastern Tibet

作　　者：王萍[1] 王慧颖 胡钢 覃金堂[1] 李翠平 WANG Ping;WANG Huiying;HU Gang;QIN Jintang;LI Cuiping(State Key Laboratory of Earthquakes Dynamics,Institute of Geology,China Earthquakes Administration,Beijing 100029,China;Chongqing Earthquake Administration,Chongqing 401147,China)

机构地区：[1]中国地震局地质研究所地震动力学国家重点实验室,北京100029 [2]重庆市地震局,重庆401147

出　　处：《地学前缘》2021年第2期35-45,共11页Earth Science Frontiers

基　　金：国家自然科学基金项目(41772199,41941017);中央级公益性科研院所基本科研业务专项重点项目(igcea1713)。

摘　　要：展布于青藏高原东南部的雅鲁藏布江流域河谷中广泛分布有古堰塞湖沉积,古堰塞湖发育与构造活动、气候变化和地表过程等因素关系密切。在广泛地质调查的基础上,识别出雅鲁藏布江流域的十余个古堰塞湖,通过对其开展沉积学、地貌学和年代学工作,结合前人工作结果,初步建立了古堰塞湖群的地层年代框架。地表残留的古堰塞湖沉积多集中于末次冰期冰盛期和全新世早期,持续时间可达千年-万年。对大竹卡古湖、格嘎古湖和易贡湖的研究结果进行了介绍,归纳出古堰塞湖群发育的基本特征,初步讨论了构造、气候和侵蚀相互作用下古堰塞湖研究的意义、存在的问题以及研究的方向。提出末次冰期以来的冰川(泥石流)堵江-堰塞-溃决洪水所构建的极端气候-灾害事件,对雅鲁藏布江河谷地貌和古地理环境等有重要影响。Lacustrine sediments of dammed paleolakes are widely distributed along the valley of the Yarlung Tsangpo River basin across the southeastern Tibetan Plateau.The development of paleolakes is closely related to tectonics,climate change,and surface processes.Through extensive geological investigation,we identified more than 10 dammed paleolakes in the Yarlung Tsangpo River basin and,combined with previous research,established the preliminary stratigraphic chronological framework of these paleolakes through sedimentological,geomorphological and geochronological studies.The remaining lacustrine sediments occurred mostly in the Last Glacial Maximum and the early Holocene,lasting from several to ten thousand years.We summarize the research results on the Dazhuka,Gega and Yigong paleolakes with a focus on their basic developmental characteristics,and discuss the significance,current challenges and research directions for studying dammed paleolakes influenced by tectonics-climate-erosion interactions.We suggest that the extreme climatic change and natural disasters,triggered by the glacial(debris flow)river damming and outburst flooding events since the Last Glacial Period,have had an significant impact on the Yarlung Tsangpo River landform and paleogeographic environment.

关 键 词：雅鲁藏布江流域 古堰塞湖 活动构造 末次冰盛期 裂点 

分 类 号：P642.2[天文地球—工程地质学] P531[天文地球—地质矿产勘探]