Method for judging risk of ice lake outburst

Abstract

The invention belongs to the field of debris flow prevention and treatment projects as well as water conservancy projects, and relates to a method for judging the risk of ice lake outburst. The method comprises the following steps: determining basic topographic data of an outburst ice lake and peripheral non-outburst ice lake through Google Earth: gradients alpha of ice lake support ice tongues and slope aspects theta of glaciers; and calculating a topographic comprehensive judgement factor S of the ice lake outburst: S=tan(alpha)+0.5sin(theta / 2), and dividing the risk of the ice lake outburst according to the topographic comprehensive judgement factor S of the ice lake outburst. According to the method for judging the risk of ice lake outburst, internal mechanism research is carried out on the degree of the ice lake outburst through researching the topographic factor, and an ice lake burst easy-happening calculation model; the topographic influence factors of the ice lake outburst are comprehensively considered, and the risk areas of the ice lake outburst are precisely divided in a quantified manner; in the formula 1, S, tan(alpha) and sin(theta / 2) are dimensionless parameters, can be used under various ice lake outburst conditions, and have stronger applicability.

Description

technical field [0001] The invention belongs to the fields of mud-rock flow prevention and control engineering and water conservancy engineering, and relates to a method for judging the risk of ice lake outburst. Background technique [0002] Glacial lake outburst is a natural phenomenon that occurs in the distribution area of ​​alpine glaciers. After the glacial lake outburst occurred, a large amount of water was released suddenly, destroying towns, burying people and animals, destroying farmland and forests, destroying bridges and roads, and blocking traffic. [0003] The occurrence of glacier lake outbursts is often due to ice avalanches or ice landslides occurring on glaciers backed by ice lakes, and two conditions need to be met for ice avalanches or ice landslides to occur: 1) terrain conditions that are conducive to ice avalanches or ice landslides; 2) certain The temperature conditions lead to cracks inside the glacier and eventually induce ice avalanches or ice lan...

AI Technical Summary

Problems solved by technology

[0004] At present, domestic and foreign researches on topographical conditions for the formation of glacial lake outbursts are mainly focused on the slope of the glacier tongue, which is a simple statistics of its development and distribution, without in-depth study of its internal mechanism (Tibetan Debris Flow and Environment, 1999: 71- 78; Hydrogeology and Engineering Geology, 2006, 3: 88-92; Glaciation and Permafrost, 2004, 26: 397-402; Acta Mountain Sinica, 2003, 21: 128-132; Glaciation and Permafrost, 1986, 8: 61-71; Acta Geographica Sinica, 1989, 44:343-352; Glaciology and Permafrost, 1987, 9:23-34; CanGeotech, 2004, 41:1068-1083; Nat Hazards, 2007, 41:131-157; Quaternary International, 2000, 65:31 -47.), the research results are difficult to apply to other regions; secondly, some scholars have conducted research on the area of ​​glacial lakes (Tibet Debris Flow and Environment, 1999: 71-78; Quaternary Research, 2003, 23: 621-628; ), the research shows that the area of ​​the ice lake is 1.89×10 5 m 3 -6.3×10 5 m 3 Best for glacial lake outbursts

In addition to the impact of the above factors on glacier lake outburst, glacier slope aspect affects the occurrence of ice avalanches or ice slides due to differences in sunlight and radiation, thus indirectly affecting glacier lake outbursts. Little research has been done on the effects of landslides

The above-mentioned rough ice tongue slope judgment method and single topographic factor research are not accurate enough to judge the risk of glacier lake outburst caused by ice avalanches or ice landslides.

Comprehensive research on the factors affecting ice avalanches or ice landslides has not been reported yet

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