Application of Scenario Earthquakes for Analysis of Seismically Triggered Landslide Hazard: A Case Study in Costa Rica

 

Guardado en:
Detalles Bibliográficos
Autores: Seal, Dylan M., Nowicki Jessee, M. Anna, Hamburger, Michael W., Ruiz, Paulo
Formato: artículo original
Estado:Versión publicada
Fecha de Publicación:2022
Descripción:In this study, we demonstrate the capabilities of hypothetical scenario earthquakes as a new tool for assessment of hazards associated with earthquake-triggered landslides. Costa Rica offers an ideal environment for demonstrating the utility of scenario earthquakes due to its diverse tectonic environments and associated widespread seismic hazard, rugged topography, and high landslide susceptibility. We investigate the relative influence of landslide proxies such as topographic slope, peak ground velocity (PGV), and compound topographic index (CTI), and earthquake source parameters such as magnitude and depth, on predicted landslide probability and fatality. We examine five distinct tectonic environments, including subduction events beneath the (1) Nicoya and (2) Osa peninsulas respectively, (3) intraplate earthquakes beneath the Central Volcanic Range (CVR) and (4) the Central Costa Rica Deformed Belt (CCRDB), and (5) back-arc thrust events on the eastern Caribbean coast. Our results demonstrate that the slope, PGV, and CTI thresholds necessary to produce landslide probabilities greater than 10% vary by tectonic environment. In all cases, we observe magnitude to be the primary control on the predicted maximum landslide probability and overall areal landslide coverage. We validate model predictions with observed landslide inventories from the 2009 Cinchona and 1991 Limon earthquakes, demonstrating a good fit, where over 70% of landslides occurring in zones of greater than 20% probability. We also use a global model of landslide impact to predict exposure and fatality ranges for each scenario earthquake of this study, revealing that moderate-sized earthquakes in the CCRDB and CVR and large subduction megathrust earthquakes each pose a significant hazard to Costa Rica’s population.
País:Portal de Revistas UCR
Institución:Universidad de Costa Rica
Repositorio:Portal de Revistas UCR
Lenguaje:Español
OAI Identifier:oai:portal.ucr.ac.cr:article/51700
Acceso en línea:https://revistas.ucr.ac.cr/index.php/geologica/article/view/51700
Palabra clave:Earthquakes
coseismic-landslides
Scenario
Natural hazards
Costa Rica
Terremotos
Deslizamientos-cosísmicos
Escenarios
Peligros