Modeling of Tsunami Propagation in the Atlantic Ocean Basin for Tsunami Hazard Assessment along the North Shore of Hispaniola

摘要

Since the devastating earthquake of 2010 in Haiti, significant efforts weredevoted to estimating future seismic and tsunami hazard in Hispaniola.In 2013, the UNESCO commissioned initial modeling studies to assesstsunami hazard along the North shore of Hispaniola (NSOH), which isshared by the Republic of Haiti (RH) and the Dominican Republic (DR).This included detailed tsunami inundation for two selected sites, CapHaitien in RH and Puerto Plata in DR. This work is reported here.In similar work done for critical areas of the US east coast (underthe auspice of the US National Tsunami Hazard Mitigation Program), theauthors have modeled the most extreme far-field tsunami sources in theAtlantic Ocean basin. These included: (ⅰ) an hypothetical M_w 9 seismicevent in the Puerto Rico Trench; (ⅱ) a repeat of the historical 1755 M_w 9earthquake in the Azores convergence zone; and (ⅲ) a hypothetical 450km3 flank collapse of the Cumbre Vieja Volcano (CVV) in the CanaryArchipelago. Here, we perform tsunami hazard assessment along theNSOH for these 3 far-field sources, plus 2 additional near-field coseismictsunami sources: (ⅰ) a M_w 8 earthquake in the western segments ofthe nearshore Septentrional fault, as a repeat of the 1842 event; and (ⅱ) aM_w 8.7 earthquake occurring in selected segments of the North HispaniolaThrust Fault (NHTF).Based on each source parameters, the initial tsunami elevation ismodeled and then propagated with FUNWAVE-TVD (a nonlinear anddispersive long wave Boussinesq model), in a series of increasingly fineresolution nested grids (from 1 arc-min to 200 m) based on a one-waycoupling methodology. For the two selected sites, coastal inundationis computed with TELEMAC (a Nonlinear Shallow Water long wavemodel), in finer resolution (down to 30 m) unstructured nested grids.Although a number of earlier papers have dealt with each of the potentialfar-field tsunami sources, the modeling of their impact on the NSOH aswell as that of the near-field sources, presented here as part of a comprehensivetsunami hazard assessment study, are novel.