GEOMORPHOLOGY APPROACH AS LANDSLIDE ASSESSMENT IN THE GEDE CATCHMENT MALANG REGENCY

Gede catchment is the part of Bromo Volcano System. It is located in the Malang Regency, East Java Province. The wide of Gede Catchment is around 17 Km2. Landslide prone area mapping shows this area has high potential landslide around 52,9%. There were several landslides which had been occurred in this area. Based on the physical condition, this area is rather not appropriate for living. The aim of this research is to elaborate geomorphology approach as landslide assessment in the Gede Catchment. The method of this research is descriptive qualitative with survey technique.  We assessed landslide based on the geomorphological approach and combined with the survey of landslide site. Based on the result shows that geomorphology is necessary factor for considering landslide assessment. Geomorphological approach is consist morphology, morphostructure, morphocronology, and morphoarrangement. The component of morphology is slope, component morphostructure and morphoarrangement is geomorphic process and for the component morphocronology is surface material and lithology. The four aspect of geomorphology become the keys for explain of landslide potential assessment. Geomorphology is the appropriate approach for landslide assessment in the Gede Catchment as the prone area for landslide. Otherwise, the potential of landslide will be difficult to determine if triggered by human activity or extreme rainfall.