降雨在时间分布的多重分形特征及对泥石流预测的指示

Study on the Multi-fractal Characteristics of the Time Distribution of Rainfall and Its Prediction Indication on Debris Flow

以2013年6月22日至7月12日四川省甘孜州海螺沟风景区热水沟发生泥石流的雨量时间序列为基础数据,引入多重分形分析方法对不同降雨过程的特征和变化趋势进行研究.研究表明不同降雨过程在特定时间段内表现出标度不变性,具有完全不同的多重分形特征;多重分形谱中的参数Δα和Δf对热水沟泥石流的发生具有指示作用,当Δα大于0.2,Δf接近0.8时热水沟会发生泥石流.多重分形谱参数可作为一个预测泥石流的定量指标,为地质灾害监测预警提供了一条新途径,对认识泥石流的发生过程和制定减灾防灾预案具有重要意义.

The rainfall characteristics are analyzed through rainfall data according to time series by muhi-fractal method from 22nd June to 12th July, 2013 in Hot-water gully, Hailuogou scenic area, Sichuan province. The analysis confirms the existence of different muhi-fractal characteristics in different rainfall process. The temporal variation of the rainfall process due to time series can be further indicated by their muhi-fractal characteristics （△α and △f） changes . The results show that it seems to trigger debris flow in Hot-water gully, when △α is greater than 0. 2 and Af is close to 0.8. Based on these results, the muhi-fractal characteristics changes of time series and scientific measurements can help forecast debris flow.