Cartography of Landslide Susceptibility around the Dias Horst and Thies Cliff-Senegal  

作　　者：Issa Ndoye Mapathé Ndiaye Déthié Sarr Papa Sanou Faye Ibrahima Khalil Cissé 

机构地区：[1]Laboratoire de Mécanique et Modélisation, UFR Sciences de l’Ingénieur, Université de Thiès, Thiès, Sénégal [2]Laboratoire de Mécanique des Sols et des Matériaux, Ecole Polytechnique de Thiès, Thiès, Sénégal

出　　处：《International Journal of Geosciences》2017年第6期821-836,共16页地球科学国际期刊（英文）

摘　　要：The aim of this work is to map the susceptibility of sites to landslides. To assess the susceptibility of the zone, GIS techniques were used. Susceptibility factors are selected and split into two groups: active and passive factors. Passive factors regroup all the intrinsic conditions existing on the field at all times. The active factors or triggering factors are present sporadically and are added to the passive factors to trigger a landslide. With the weighted overlay method using ArcGIS?, four scenarios have been developed. A first scenario where only passive factors are combined and three scenarios for which we have for each scenario the passive factors combined with an active factor. With these different scenarios, five levels of susceptibility are obtained in the zone. These levels range from very low to very high susceptibility. For the different scenarios, the results show that the zone consists mainly of very low to low susceptibility with at least 61% of the area, followed by moderate susceptibility (23.54% to 38.24%) and last land with high susceptibility to very high with less than 1% of the surface. Fields with high to very high susceptibility are located on the slopes of the hills. Among the active factors, only the rainfall significantly modifies the percentage of land susceptible to landslide but remains in the field of moderate susceptibility. The predicted susceptibilities are closer to the observed landslides around the Thies Cliff than to the Dias Horst.The aim of this work is to map the susceptibility of sites to landslides. To assess the susceptibility of the zone, GIS techniques were used. Susceptibility factors are selected and split into two groups: active and passive factors. Passive factors regroup all the intrinsic conditions existing on the field at all times. The active factors or triggering factors are present sporadically and are added to the passive factors to trigger a landslide. With the weighted overlay method using ArcGIS?, four scenarios have been developed. A first scenario where only passive factors are combined and three scenarios for which we have for each scenario the passive factors combined with an active factor. With these different scenarios, five levels of susceptibility are obtained in the zone. These levels range from very low to very high susceptibility. For the different scenarios, the results show that the zone consists mainly of very low to low susceptibility with at least 61% of the area, followed by moderate susceptibility (23.54% to 38.24%) and last land with high susceptibility to very high with less than 1% of the surface. Fields with high to very high susceptibility are located on the slopes of the hills. Among the active factors, only the rainfall significantly modifies the percentage of land susceptible to landslide but remains in the field of moderate susceptibility. The predicted susceptibilities are closer to the observed landslides around the Thies Cliff than to the Dias Horst.

关 键 词：CARTOGRAPHY SUSCEPTIBILITY LANDSLIDES Dias HORST Thies CLIFF 

分 类 号：R73[医药卫生—肿瘤]