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

Grilli, Annette R. (University of Rhode Island) | Grilli, Stéephan T. (University of Rhode Island) | David, Eric (Artelia) | Coulet, Christophe (Artelia)

OnePetro 

Abstract

Since the devastating earthquake of 2010 in Haiti, significant efforts were devoted to estimating future seismic and tsunami hazard in Hispaniola. In 2013, the UNESCO commissioned initial modeling studies to assess tsunami hazard along the North shore of Hispaniola (NSOH), which is shared by the Republic of Haiti (RH) and the Dominican Republic (DR). This included detailed tsunami inundation for two selected sites, Cap Haitien in RH and Puerto Plata in DR. This work is reported here.

In similar work done for critical areas of the US east coast (under the auspice of the US National Tsunami Hazard Mitigation Program), the authors have modeled the most extreme far-field tsunami sources in the Atlantic Ocean basin. These included: (i) an hypothetical Mw 9 seismic event in the Puerto Rico Trench; (ii) a repeat of the historical 1755 Mw 9 earthquake in the Azores convergence zone; and (iii) a hypothetical 450 km3 flank collapse of the Cumbre Vieja Volcano (CVV) in the Canary Archipelago. Here, we perform tsunami hazard assessment along the NSOH for these 3 far-field sources, plus 2 additional near-field coseismic tsunami sources: (i) a Mw 8 earthquake in the western segments of the nearshore Septentrional fault, as a repeat of the 1842 event; and (ii) a Mw 8.7 earthquake occurring in selected segments of the North Hispaniola Thrust Fault (NHTF).

Based on each source parameters, the initial tsunami elevation is modeled and then propagated with FUNWAVE-TVD (a nonlinear and dispersive long wave Boussinesq model), in a series of increasingly fine resolution nested grids (from 1 arc-min to 200 m) based on a one-way coupling methodology. For the two selected sites, coastal inundation is computed with TELEMAC (a Nonlinear Shallow Water long wave model), in finer resolution (down to 30 m) unstructured nested grids. Although a number of earlier papers have dealt with each of the potential far-field tsunami sources, the modeling of their impact on the NSOH as well as that of the near-field sources, presented here as part of a comprehensive tsunami hazard assessment study, are novel.