The potential of landslide in Lake Maninjau Catchment Area, West Sumatra

Abstract

West Sumatra is amongst tectonically and volcanically active area, located at the interface of Indo-Australia and Eurasia plates. The movement of plates triggers many natural disasters, one of them is landslides. Especially Lake Maninjau that located in Tanjungraya District, Agam Regency, West Sumatra that often experience the landslide. This landslide caused physical damage and loss of life. The direct research was conducted in the field by mapping rock types, soil types, slope and then other factors such as rainfall and landuse, using Geographic Information System (GIS) based analysis using the weighted method with spatial analysis, and weighting for each parameter. The higher score and the weight, then the effect will be higher on the ground movement and vice versa. The purpose of this research is to get information about potential of landslide as the basis for the development of Lake Maninjau Watershed Area. Based on the result of DEM analysis the research area is dominated by a fairly steep slope (15%-30%) whereas the area with flat slope - very flat only 20% of 244,03 km2. Landuse as settlement, plantation, forest, water etc. Result of this research with spatial analysis is potential of ground motion in 20 locations with steep slopes around Koto Malintang Village and Tanjung Sani Village. The validation of calculation result shows 75% similarity with field data.