Development of seismic microzonation maps using geographic information systems (GIS) for Banda Aceh City, Indonesia

Abstract

The location of Banda Aceh which lies about 100km from Sumatra Subduction Zone and very close to the Sumatran Transform Faults which is about 10km makes this place extremely vulnerable to earthquake hazards. Learning from the experience of earthquake and tsunami on 26 January 2004 which caused many deaths, property loss and devastation of the city, therefore, urban planning and development in the future should take into consideration the earthquake hazards. Based on this purpose, seismic microzonation maps which are capable of identifying and mapping different earthquake hazard potentials can be used as an initial phase for earthquake risk mitigation. The purpose of this study is to create seismic microzonation maps using Geographic Information Systems (GIS) and in turn can be used as guidance in urban planning and development. The maps were developed through a series analysis of the parameters that influence the earthquake hazards which includes seismological data, such as Peak Ground Acceleration (PGA), faults, tsunami, and site characteristic data such as geotechnical data (soil type, site class, groundwater distribution and depth), geological data, and geophysical data (contour or slope). The maps produced encompasses the variations of earthquake hazard such as ground shaking hazard map, liquefaction susceptibility hazard map, landslide potential hazard map, surface faulting hazard map and tsunami hazard map. The resulting maps identified three levels of hazards (low, medium and high hazard). Identifying the variation in earthquake hazards makes it possible to select relatively safe zones for future development and some recommendations should be taken into cognizance in carrying out any development in the medium or high hazard zone areas.