安县高川河流域泥石流物源特征及其活动量预测

汶川地震后,地震灾区次生地质灾害十分活跃,尤其是泥石流灾害,呈现出爆发频繁、规模巨大、影响周期长等特点,究其缘由,主要与地震产生的大量物源有关。以绵阳市安县高川河流域8条主要泥石流沟为例,通过现场实际调查,结合遥感影像,统计了研究区内泥石流物源情况,得到了各泥石流沟的物源总量及动储量。从统计结果看,研究区内各泥石流沟物源均较为丰富,具备再次发生大规模泥石流的条件;研究区泥石流物源主要来自于地震崩滑体,通过对崩滑物源的统计分析,发现其分布表现出明显的高程效应、坡度效应、坡体结构效应以及上下盘效应。并在此基础上,基于灰色理论,建立了研究区泥石流活动物源量的GM(1,5)预测模型,通过残差验证,证明了该模型具有较高可信度。

Characteristics of Debris Flow Provenance and Activity Prediction of Gaochuan River Basin in Anxian County

After Wenchuan earthquake, the secondary geological disasters occurred frequently, especially the debris flow disasters. It presents the characteristics of frequent outbreak, huge scale, and long influence cycle. The main reason is related to the large provenance of earthquake. Taking eight main debris flow gullies in Gaochuan river basin as the research objects, by actual site survey and combination with remote sensing images, the provenance of debris flows in the study area were carried out a detailed statistics and it got the total provenance and the activities provenance amount of each debris flow. According the statistical results, the provenance of each gullies are abundant to initiate debris flows again. The main provenance is come from the earthquake landslides and rockfalls in study area. It found out that the distribution of provenance has the effect of elevation, slop, structure and footwall. According to the grey theory, the GM(1,5) prediction model of the activity provenance in study area is built up, and the model has high reliability by verification of the residual error.