Abstract Database

TSUNAMI DAMAGE ESTIMATION IN MANTA, ECUADOR USING FRAGILITY FUNCTIONS

MEE15621
Sharl Narvet Noboa Teran
Supervisor: Shunichi Koshimura
Country: Ecuador
Abstract

We performed a parametric study using linear and non linear numerical simulations to find the possible worst tsunami scenario that could affect the central coasts of Ecuador. From the calculation of seafloor deformation and the results of maximal tsunami heights at coastal points, we obtained that earthquakes of Magnitude greater than Mw 8.0 caused the maximal values. Then we used events of Magnitude Mw 8.8 as seismic sources to run nonlinear simulations. These simulations got values of inundation depth, necessary for the estimation of tsunami building damage and casualties using fragility functions. We compared the inundation area of the three scenarios that got the maximal values of inundation depth and then we applied the fragility functions of Banda Aceh to each scenario. The worst scenario that caused more damage in buildings and casualties corresponds to an earthquake of Mw 8.8, with its SW edge fault, settled at 81.26° W longitude and 0.59° S latitude with a focal depth of 14 km. The assumed slip was 10 meters for a rupture of 400 km in length and 160 km in width. The strike was parallel to the Nazca trench, 23°; the characteristic dip was 16° and the rake was 90°. This hypothetical event generated waves up to 5 meters high at the coast of Manta and caused an inundation extension of 3.05 km2 in the coastal sectors of Manta. All the models represent the great threat of inundation for the beautiful beaches of Manta. We obtained that in the coastal sectors, 13% of the population would be killed and 24.42% of houses would be damaged if an earthquake of Mw 8.8 generates a tsunami.   

 

Keywords:  Ecuador, Tsunami, Fragility function, Damage estimation