ANALISIS POTENSI BAHAYA TSUNAMI DI KABUPATEN KEPULAUAN MENTAWAI (STUDI KASUS: DESA SIOBAN, DESA MATOBE, DAN DESA ROKOT)

• Main Author: Rizky Arifianto, Muhammad
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/40108
• Institution: Institut Teknologi Bandung

Mentawai Islands Regency is one of the areas that has a potential disaster like earthquake and tsunami. Strain accumulation around the Mentawai Islands at any time can be released in the form of earthquakes. The high potential of the earthquake can trigger a tsunami, especially for areas that are on the coast. These coastal disasters can cause fatalities if disaster mitigation efforts are not carried out properly. Therefore, as a first step in a disaster risk reduction program, an analysis of the potential for natural disasters, especially tsunami hazards, must be carried out with the aim of knowing how the danger level can be caused and how much influence it has on the available evacuation points and accesses. Analyze the potential of a tsunami hazard can be done by making an approach through numerical simulations to obtain potential tsunami hazards as seen from the distribution value of tsunami inundation height and range, tsunami run-up value, and estimated tsunami arrival time. The method used is quantitative by using bathymetric data, topography data, and earthquake parameters. Numerical simulations were carried out using the COMCOT model with 3 earthquake scenarios for 3 study areas the historical scenario of the 2010 mentawai earthquake, the subduction zone earthquake scenario, and the earthquake scenario of the mentawai fault zone. Based on the 3 earthquake scenarios, subduction zone scenario is the scenario with the highest potential hazard. From this study, Sioban Village obtained the maximum tsunami inundation height was 4.1 m, the maximum inundation range value was 233.5 m, the maximum run-up value was 5.5 m, and the tsunami arrival time was around 9 minutes in Sioban Village. Then in Matobe Village, it has a potential tsunami hazard with a maximum inundation value of 3 m, a maximum inundation range value of 235.1 m, a maximum run-up value of 3.6 m, and a tsunami arrival time of around 9 minutes. Whereas for Rokot Village has a potential tsunami hazard with a maximum inundation value of 2.2 m, the maximum inundation range value is 275.7 m, the maximum runup value is 2.9 m, and the tsunami arrival time is around 9 minutes. The results of the analysis of potential tsunami hazards also indicate that the 3 evacuation sites currently in Sioban Village are in a safe area because they are not in the tsunami coverage area, while in Matobe Village there are 2 safe areas while 1 area is only temporary. Then for Rokot Village, 1 evacuation gathering point is quite safe because in the surrounding area there is a puddle of low grade below 1 m.