雅鲁藏布江米林段泥石流堆积扇危险范围预测模型

PREDICTION MODEL FOR DEBRIS FLOW HAZARD ZONE ON ALLUVIAL FAN IN MILIN SECTION OF YARLUNGZANGBO RIVER,TIBET

雅鲁藏布江米林段紧邻印度板块与欧亚板块碰撞带,地势复杂,构造运动强烈,地震活动频繁,因此泥石流分布广泛。本文经过遥感与野外实际调查,以研究区的34条泥石流沟为样本进行分析,利用GIS与RS软件对研究区内的泥石流流域高差、物源量等基本参数进行数据采集与分析,确定相关因子后,利用Mat lab软件进行泥石流最大冲出长度、最大冲出宽度与其相关因子的回归分析,发现泥石流最大冲出长度、最大冲出宽度与流域高差、物源量之间具有明显的指数相关的关系,从而建立泥石流危险范围的预测模型。该模型在吸纳前人模型的基础上,采用较少的因子就能够判别研究区泥石流的危险性范围,缩短了判断泥石流危险性范围的时间,更加有利于快速防灾避险。

The Milin county along Yarlungzangbo river is closed to the Indian plate with the Eurasian plate collision zones, where the tectonic movement is intense and the seismic activity is frequent. So debris flow are widely distributed. This paper uses the remote sensing and field investigation and examines 34 debris flow gullies which have an integrated deposit fan. Using geographical information system and remote sensing software, the paper analyses the basic parameters of the basin such as basin relief and the volume source. The regression analysis on the maximum length and width runout and their topographical factors is conducted using the software Mat lab. It is found that the maximum length and width runout have an obvious index correlation with the basin relief and the volume source. Based on the found single factor regular, the predicting model on evaluating the debris flow＇s hazardous range is established. This model absorbs the previous model advantages, distinguishes the risk range by less factors and saves time. It can be better and faster against the disaster.