Articles | Volume 17, issue 6
Research article
08 Jun 2017
Research article |  | 08 Jun 2017

Empirical prediction for travel distance of channelized rock avalanches in the Wenchuan earthquake area

Weiwei Zhan, Xuanmei Fan, Runqiu Huang, Xiangjun Pei, Qiang Xu, and Weile Li

Abstract. Rock avalanches are extremely rapid, massive flow-like movements of fragmented rock. The travel path of the rock avalanches may be confined by channels in some cases, which are referred to as channelized rock avalanches. Channelized rock avalanches are potentially dangerous due to their difficult-to-predict travel distance. In this study, we constructed a dataset with detailed characteristic parameters of 38 channelized rock avalanches triggered by the 2008 Wenchuan earthquake using the visual interpretation of remote sensing imagery, field investigation and literature review. Based on this dataset, we assessed the influence of different factors on the runout distance and developed prediction models of the channelized rock avalanches using the multivariate regression method. The results suggested that the movement of channelized rock avalanche was dominated by the landslide volume, total relief and channel gradient. The performance of both models was then tested with an independent validation dataset of eight rock avalanches that were induced by the 2008 Wenchuan earthquake, the Ms 7.0 Lushan earthquake and heavy rainfall in 2013, showing acceptable good prediction results. Therefore, the travel-distance prediction models for channelized rock avalanches constructed in this study are applicable and reliable for predicting the runout of similar rock avalanches in other regions.

Short summary
Channelized rock avalanches are a type of rock slope failures with massive flow-like movements of fragmented rock, which are potentially dangerous due to their strong mobility. This study built an empirical prediction model of travel distance using the Wenchuan earthquake dataset. The results suggest that the movement was dominated by the landslide volume, total relief and channel gradient. The model was tested by a separate dataset and proved to be useful in other regions as well.
Final-revised paper