文家坝大型单体滑坡地质特征遥感调查与稳定性分析

RS-BASED GEOLOGICAL FEATURES INVESTIGATION AND STABILITY ANALYSES IN WENJIABA LANDSLIDE

平武县的文家坝滑坡是由汶川地震诱发,并曾阻断河流形成文家坝堰塞湖,威胁到下游南坝、锰矿厂和公路的安全,所以有必要对其地质特征进行调查及稳定性分析。通过对震后平武县SPOT卫星影像的解译,识别出了文家坝滑坡的地貌要素及滑坡物质组成,表面植被发育度,水文条件等地质特征。可以认为,文家坝滑坡为大型牵引式滑坡,目前仍处于不稳定状态,在余震、强降雨等条件下,有复滑的可能,并针对潜在威胁给出了具体的防治建议。

The Wenjiaba landslide of Pingwu County was triggered by Wenchuan earthquake,and when it occurred it has blocked the river and formed a barrier lake which brought the risky for Nanba town and a manganese factory at downstream.So it is necessary to investigate the geological features and to analysis the stability of the landslide.By interpreting a post-earthquake SPOT image of Pingwu County,the geological features,such as the geomorphic factors,the material composition,the vegetation coverage and the hydrological condition were identified.On the base of that,Wenjiaba landslide was considered as a large retrogressive landslide and was still not stable at present,it may be re-slide on a certain condition.Some prevention suggestions for potential risks was proposed in the final.