MAPPING FAULTS DISTRIBUTION BASED ON DEM DATA FOR REGIONAL SPATIAL PLAN ASSESSMENT OF SABANG MUNICIPALITY, INDONESIA

Abstract

Sabang Municipality is located on Weh Island. As a maritime gateway to Indonesia, the island has been inaugurated as an Integrated Economic Development Zone by the Government. A complete infrastructure has been planned and built to support the manufacturing and tourism industries in the region. On the other hand, the island is potentially affected by geological hazards. Tectonically, the island is crossed by the Great Sumatran Fault (GSF), but few studies have shown the fault trace on the island. To ensure sustainable development, such potential geological hazards have to be incorporated into the Regional Spatial Plan (RSP) of the city. In this study, fault distribution on the island were mapped using shaded relief, slope, lineament extraction, orientation, and Fault Fracture Density (FFD) distribution extracted from the National Digital Elevation Model (DEMNAS) data. The map shows that the island is crossed by several fault lines, but the one located along the eastern with northwest-southeast direction is considered tectonically active. However, according to the RSP, the eastern Weh Island is the most developed area. The city center, airport, seaports, dam, sewerage treatment plan, landfills, and diesel power electricity generator for the city are situated along this fault line. It seems that the RSP of Sabang Municipality was issued without taking into account potential geological hazard maps in it. Some recommendations have been proposed to reduce the impact of losses in the future.