Identification of surface layer structure using seismic refraction for landslide mitigation in Tandikek region, West Sumatra Indonesia

Abstract The landslide in West Tandikek Nagari, Padang Pariaman Regency, 2009 was triggered by an earthquake that claimed hundreds of lives and buried several villages. Losses caused landslides Nagari should be minimized studying the causes symptoms landslides. Disaster mitigation efforts must carried out to anticipate mitigate losses due so impacts can overcome. These disaster actions identifying areas with potential for based on subsurface structure Nagari. This type research descriptive. Data collection is directly using Sysmatrack-MAE Seismograph, 12 geophones, GPS, gauges, trigger cables, geophone sources form a seismic hammer iron plate refraction method. processing obtain velocity depth values each track below surface method interpretation used Time-Term Inversion. results obtained first layer are dominated sand soil materials. second alluvium gravel clay. relatively hard clay makes it difficult store pass water. will cause water from top accumulate rock, which rock slippery. slippery act as weathering material above move hillside