Tsunami Risk for Chile’s Coastal Areas


Abstract eng:
Chile is affected by destructive earthquakes; of these earthquakes, those occurring offshore have the potential to generate destructive tsunamis. To assess the risk of tsunami damage generated by subduction seismic events, several analyses have been conducted on eleven major Chilean coastal cities. From the characterization of five mega-thrust events occurring due to the subduction of the Nazca plate below the South American plate, Okada’s rupture model is applied as the initial boundary condition to five regional numerical models representing massive water waves propagating towards the continent. The mega-thrust events were characterized to represent a code-level earthquake, but not the maximum historical earthquake (1960 Valdivia earthquake, Mw=9.5). Using the results of these five regional models as boundary conditions, eleven refined numerical models were used to compute the onshore water invasion and the velocity of impact on the infrastructure encountered. On both, regional and local models, the most accurate bathymetry of the ocean floor was used; similarly, the up-to-date coastline geometry, onshore topography, and infrastructure localization were included. The infrastructure was assumed to be reflective. The models were built and analyzed using state-of-the-art technology to represent the boundary conditions, water domains, seafloor bathymetry, and onshore topography and geometry, as accurately as needed. The models were successfully verified with data observed after the 2010 Maule earthquake (Mw=8.8). The results obtained indicated that most of the eleven cities studied were relatively safe from the destructive damage that these types of tsunamis generate, mostly due to the hilly geography of Chile’s coastal region. However, the areas, and infrastructure on the coastline such as ports, would be subjected great damage. The eleven coastal cities studied were: Arica, Iquique, Mejillones, Antofagasta, La Serena, Coquimbo, Quintero, Viña del Mar, Valparaíso, San Antonio, and Talcahuano.

Contributors:
Conference Title:
Conference Title:
16th World Conference on Earthquake Engineering
Conference Venue:
Santiago (CL)
Conference Dates:
2017-01-09 / 2017-01-13
Rights:
Text je chráněný podle autorského zákona č. 121/2000 Sb.



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 Record created 2017-01-18, last modified 2017-01-18


Original version of the author's contribution as presented on USB, paper 2442.:
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