| CRITICAL HYDROLOGIC CONDITIONS FOR OVERFLOW BURST OF MORAINE LAKE |
| |
| 作者姓名： | JIANG Zhong-xin CUI Peng JIANG Liang-wei |
| |
| 作者单位： | 1.The No.2 Survey and Design Institute of Ministry of Railway，Chengdu 610031，P.R.China;2.Institute of Mountain Hazards and Environment，Chinese Academy of Sciences，Chengdu 610041，P.R.China;3.Southwest Jiaotong University，Chengdu 610031，P.R.China |
| |
| 基金项目： | Foundation term: Under the auspices of the Knowledge Innovation Program of Chinese Academy of Sciences(KZCX2-306) |
| |
| 摘 要： | 1OVERFLOWBURSTOFMORAINELAKEFloodwater and debris flow caused by glacial lake burst is an important land process and a serious moun-tain disaster in glacial area. Glacial lakes with burst can divided into the glacier-obstructed lake (ice dam lake) and the terminal moraine lake (XU and FENG, 1988). Typical burst of ice dam lake happens in the modern glacier area of the upper reaches of the Kele-qing River in Uygur Autonomous Region of Xinjiang (WANG, 1990). But most of burst gla…
|
| 关 键 词： | 水文地质 洪水 冰湖 终碛 |
| 收稿时间： | 6 June 2003 |
Critical hydrologic conditions for overflow burst of moraine lake |
| |
| JIANG Zhong-xin,CUI Peng,JIANG Liang-wei.CRITICAL HYDROLOGIC CONDITIONS FOR OVERFLOW BURST OF MORAINE LAKE[J].Chinese Geographical Science,2004,14(1):39-47. |
| |
| Authors: | Jiang Zhong-xin Cui Peng Jiang Liang-wei |
| |
| Institution: | (1) The No.2 Survey and Design Institute of Ministry of Railway, 610031 Chengdu, P. R. China;(2) Institute of Mountain Hazards and Environment, Chinese Academy of Sciences, 610041 Chengdu, P. R. China;(3) Southwest Jiaotong University, 610031 Chengdu, P. R. China |
| |
| Abstract: | Floodwater and debris flow caused by glacial lake burst is an important land process and a serious mountain disaster in glacial area of Xizang (Tibet) Autonomous Region, and the overflow burst is mainly caused by glacial landslide falling into moraine lake. On the premise that moraine lake is full, instantaneous burst in part of the lake bank happens, as flow velocity at burst mouth caused by overflow head is higher than threshold flow velocity of glacial till. Under some supposes, d90 and d10 of the glacial till in the bank were used as the threshold sizes of coarse and fine grains respectively. Thus, the formula of calculating threshold flow velocity of uniform sand was simplified, and threshold flow velocity of glacial till was calculated with the formula. Then, with synthesis formula calculating flow velocity of instantaneous part burst, flow velocity at overflow burst mouth was calculated, and calculation formula of critical height (H0) of overflow head was derived. Overflow head was caused by volume and surge of glacial landslide falling into moraine lake, calculation formulas of ascendant height (H1) of lake water surface and surge height (H2) on burst mouth caused by glacial landslide falling into moraine lake were derived. To sum up, critical hydrologic conditions of moraine lake burst with overflow form are: the burst is inevitable as H1 >H0; the burst is possible as H1 H0; the burst is impossible as (H1 H2)
|
| |
| Keywords: | moraine lake terminal moraine bank overflow burst critical height of overflow head glacial landslide Guangxiecuo Lake |
| 本文献已被 CNKI 万方数据 SpringerLink 等数据库收录！ |
