摘要
黄河上游夏藏滩巨型古滑坡的发育特征、形成机制与演化过程在尖扎盆地具有典型性，是研究黄河上游巨型滑坡与气候变化的理想之地。文章通过野外详细调查、地质勘查、实验测试和遥感解译等工作开展了该滑坡体的发育特征、运动分区、演化过程和形成机制研究，主要取得了以下认识：1）夏藏滩巨型滑坡分两个期次发育，其中Ⅰ期的发生时间为50kaB．P．，为整体滑动，体积约14．56×10^8m3，周界在平面上形似“圈椅型”，滑坡在剪出口启动的速度为66．11m／s，属于高速远程滑坡类型，Ⅱ期滑坡是Ⅰ期前缘的解体滑坡，发生于约30kaB．P．；2）夏藏滩滑坡经历了占滑坡“孕育”、Ⅰ期滑坡发生与“滑坡湖”形成、Ⅱ期解体滑坡发生和Ⅰ期滑坡“滑坡湖”消失等4个地形地貌演变阶段；3）夏藏滩Ⅰ期滑坡受控于50kaB．P．左右气候变化中的暖湿期降水和盆地内锁子滑坡堰塞湖库水位下降共同制约，Ⅱ期滑坡因MIS3a阶段“高温大降水事件”诱发。
The developmental characteristics, formation mechanism and evolution process of the Xiazangtan ancient super large scale landslide located at the upper reaches of Yellow River is a typical and representative case in the Jianzha basin, northeast Tibet Plateau of China. In this paper, through meticulous field surveys, geological exploration, laboratory testing, and remote sensing interpretation and other ways to carry out the developmental characteristics, moving regions, evolution process and formation mechanism of this landslide, and mainly achieved the following conclusions： （1） There are two developmental stages of Xiazangtan super large scale landslide, and the first stage occurred about 50ka B.P. with whole volume of about 14.56×10^8m3 and sliding distance was 8.16km, the surface plane likes arm-chair type with the moving speed of 66.11m/s in the back sheering crack opening, therefore, the first stage is a high-speed long run-out landslide. The second stage occurred about 30ka B.P. and belonged to the disintegration landslide in front of the first stage. （2） There were four phases in the Xiazangtan landslide forming processes, they are ancient landslide deforming and failing phase, the first stage of landslide occurred and the landslide lake formed in the back mass, the second stage of landslide happened and the landslide disappeared. （3） The first stage of Xiazangtan landslide controlled by the warm and humid climate change on rainfall in the 50ka B.P. and Suozi landslide drawdown of damming lake water level located also the Jiazhan basin, and the second stage was triggered by the highly precipitation in the Marine Isotope Stage 3a.
出处
《第四纪研究》
CAS
CSCD
北大核心
2016年第2期474-483,共10页
Quaternary Sciences
基金
国家自然科学基金项目（批准号：41372333）、国土资源部中国地质调查项目（批准号：1212011220123）和成都理工大学地质灾害防治与地质环境保护国家重点实验室开放基金项目（批准号：SKLGP2013K024）共同资助
致谢真诚地感谢审稿专家建设性的修改意见和编辑部老师细致的编辑.
关键词
夏藏滩
巨型滑坡
发育特征
形成机制
演化过程
Xiazangtan, super large scale landslide, developmental characteristics, forming mechanism evolution process
