R. Irvan Sophian
Padjadjaran University in Indonesia,
Email: [email protected]
Padjadjaran University in Indonesia
In Indonesia, West Java Province is well known for the most frequent landslide occurrence from time to time. Physically destructed land by such the geological hazard could widely affect people and infrastructures. In the eastern part of West Java landslide frequently occurs in the Citanduy River catchment area. This phenomenon is approached through slope stability analysis.Quantitative analysis of slope stability (FS) and plotting of previous landslides occurrences on geological map are carried out to produce slope stability zonation map. Conditions of geomorphology, hydrogeology, soil types and their distribution, and also current landuse are considered as supported data. As the result of analyses three zones of slope stability can be obtained and mapped in the study area. The respective areas of distribution of FS of more than 1.25, FS ranging from 1.1 to 1.25, and FS from 1.0 to 1.1 are stable-, critical to stable-, and critical zones. FS of less than 1.0 means unstable slope where landslide occurs. Stable zone is characterized by plain area on thin and coarse grain soil. Critical to stable zone is of hilly to mountainous land predominantly consisting of fine grain thick residual soil of sedimentary or volcanic rocks. Critical zone is of swelling-shrinking type of thick soil on high-angle slope, high density of deformation pattern of geological structures, high run-off caused by drainage on the top of slope (ponds, paddy fields, etc).
Keywords: Landslide, Slope Stability, Citanduy River, Safety Factor