Sedimentary records of a palaeo-lake in the middle Yarlung Tsangpo: Implications for terrace genesis and outburst flooding
Sedimentary records of a palaeo-lake in the middle Yarlung Tsangpo: Implications for terrace genesis and outburst flooding
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雅鲁藏布江中部古湖泊的沉积记录：对阶地成因和溃决洪水的启示
DOI：
10.1016/j.quascirev.2018.05.037
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发表时间：
2018-07
影响因子：
4
通讯作者：
Chen Feng
中科院分区：
文献类型：
--
作者：
Hu Hai Ping;Feng Jin Liang;Chen Feng
青藏高原南部雅鲁藏布江中游地区由宽阔的河谷河段组成，与峡谷相间，在末次冰期很容易被冰川和/或冰川冰川所阻挡。我们研究了雅鲁藏布江中游日喀则河谷宽阔河段和大竹卡-月居峡三个古湖泊沉积层序。发现该古湖海拔3811 m，最小面积为∼679 km2，最小体积为∼22 km2。该古湖形成于约30.2~32.3 cal. KYR BP，约13.2 cal. KYR BP。大坝可能位于大竹卡-越桔峡谷的东端，可能是上一次冰川晚期的冰川和/或冰川。大坝的坍塌和来自大竹卡-越桔峡谷的相关洪水可能引发了下游大坝坍塌的连锁反应，形成了一场特大洪水。研究区阶地成因和河谷演化可划分为4个阶段：Ⅰ期(&Gt；32.3 Cal. Kyr BP)，河流占位；Ⅱ期(<；32.3-13.2 Cal. Kyr BP)，古湖泊占据；Ⅲ期(13.2 Cal. Kyr BP之后)，侵蚀和风成沉积；Ⅳ期，现代下切。
The middle reaches region of the Yarlung Tsangpo in the southern Tibetan Plateau consist of broad valley reaches, alternating with gorges, which were easily dammed by glaciers and/or glacial moraines during the last glacial period. We investigated three palaeo-lake sedimentary sequences on terraces located in the broad Xigazê valley reach and the Dazhuka-Yueju gorge in the middle reaches of the Yarlung Tsangpo. We found that the altitude of the palaeo-lake was 3811 m above sea level, while its minimum area and volume were ∼679 km2and ∼22 km3, respectively. The palaeo-lake was formed during the period from about 30.2 to 32.3 cal. kyr BP, and it failed at about 13.2 cal. kyr BP. The dam was possibly located at the eastern end of the Dazhuka-Yueju gorge and may have been a glacier and/or a moraine during the late part of the last glacial. The failure of the dam and related flooding from the Dazhuka-Yueju gorge probably triggered a chain reaction of dam failures downstream, forming a megaflood. Terrace genesis and valley evolution in the investigated region can be divided into four phases: Phase Ⅰ (>32.3 cal. kyr BP), river occupation; Phase Ⅱ (<32.3–13.2 cal. kyr BP), palaeo-lake occupation; Phase Ⅲ (after 13.2 cal. kyr BP), erosion and aeolian deposition; Phase Ⅳ, modern downward incision.
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影响因子：
8.3
作者：
TALMA, AS;VOGEL, JC
通讯作者：
VOGEL, JC
影响因子：
2.3
作者：
D. Leverington;J. Mann;J. Teller
通讯作者：
D. Leverington;J. Mann;J. Teller
DOI：
--
发表时间：
1988
期刊：
--
影响因子：
--
作者：
L. Owen
通讯作者：
L. Owen
影响因子：
2.2
作者：
Zhu Song;Wu Zhen-han;Zhao Xitao;Xiao Ke-yan
通讯作者：
Zhu Song;Wu Zhen-han;Zhao Xitao;Xiao Ke-yan
影响因子：
5.8
作者：
A. Draut;P. Clift
通讯作者：
A. Draut;P. Clift