Development characteristics and potential risks of Dankanongba glacial lake in Bomi, Tibet

Glacial lake outburst flood (GLOF) is one of the serious mountain disasters in the Qinghai-Tibet Plateau, which seriously threatens the safety of the Sichuan-Tibet arterial traffic which is under construction recently.Therefore, it is necessary to carry out professional investigation and assessment of these potential hazard glacial lakes above the railway, and formulate targeted prevention and control countermeasures.The Dankanongba glacial lake in Bomi was selected as the research object, through remote sensing interpretation, field investigation, engineering geological analogy and numerical simulation, to investigate the background characteristics of glacial lake, glacier and snow covered zones, formation and transportation zones and accumulation zones.It is proposed that Dankarongba has the conditions for glacial lake breach and debris flow formation.It is also revealed that high-place glacier collapse, glacier surge and snow avalanche are the main inducement types of GLOF.Based on the calculation of flood discharge of the end moraine breach, the evolution process of debris flow in the downstream channel is also simulated.The results of numerical calculation and analysis show that the debris flow formed under the condition of GLOF will cause direct damage to 85 people of 28 households in the accumulation area.It will also cause diversion of the main stream and indirect damage to the Sichuan-Tibet arterial traffic and their ancillary facilities by the right bank of the river.A preliminary exploration on how to carry out disaster investigation and potential assessment in the glacial lake areas above the Sichuan-Tibet arterial traffic is carried out, which can be used for reference in the natural resource management, water conservancy and hydropower development, glacial lake scenic spot location and other glacial lake disaster assessment in Tibet.