Assessment of tsunami hazards for the Central American Pacific coast from southern Mexico to northern Peru

S. Tinti,A. Armigliato,B. Brizuela

doi:10.5194/nhess-14-1889-2014

Abstract

Abstract. Central America (CA), from Guatemala to Panama, has been struck by at least 52 tsunamis between 1539 and 2013, and in the extended region from Mexico to northern Peru (denoted as ECA, Extended Central America in this paper) the number of recorded tsunamis in the same time span is more than 100, most of which were triggered by earthquakes located in the Middle American Trench that runs parallel to the Pacific coast. The most severe event in the catalogue is the tsunami that occurred on 2 September 1992 off Nicaragua, with run-up measured in the range of 5–10 m in several places along the Nicaraguan coast. The aim of this paper is to assess the tsunami hazard on the Pacific coast of this extended region, and to this purpose a hybrid probabilistic-deterministic analysis is performed, that is adequate for tsunamis generated by earthquakes. More specifically, the probabilistic approach is used to compute the Gutenberg–Richter coefficients of the main seismic tsunamigenic zones of the area and to estimate the annual rate of occurrence of tsunamigenic earthquakes and their corresponding return period. The output of the probabilistic part of the method is taken as input by the deterministic part, which is applied to calculate the tsunami run-up distribution along the coast.

Highlights

This paper is concerned with the tsunami hazard in the Extended Central America (ECA) region that extends from southern Mexico to northern Peru
At the end of the analysis, by combining the results obtained for the rate of tsunamigenic earthquakes on a trench segment and the generation and amplification of the tsunami along the corresponding profile to the coast, we can calculate the occurrence probability of run-up exceeding a given value for the corresponding coastal segment as well as other related quantities, including the run-up distribution along the coast corresponding to a given return period, which is very important for engineering and civil protection reasons
The first provides a comparative view of the lowest value for the maximum expected run-up for different recurrence times in a geographical perspective, while Fig. 10 shows a simplified 2-D representation of the expected run-up height distribution along the coast of the ECA from central Mexico to northern Peru, embracing the entire Pacific coast of Central America

Summary

Introduction

This paper is concerned with the tsunami hazard in the Extended Central America (ECA) region that extends from southern Mexico to northern Peru. Satake, 1994; Piatanesi et al, 1996), this event triggered tsunami research in the ECA, including the compilation of a regional tsunami catalogue (Molina, 1997) for Central America (CA), that is the region going from Guatemala to Panama, and empirical, statistical and deterministic tsunami assessments. Preliminary tsunami hazard estimations were performed on the Pacific coast in 2000 by the Centro de Investigaciones Geofísicas (CIGEFI) de la Universidad de Costa Rica, the Red Sismológica Nacional (RSN: ICE-UCR), the Instituto de Sismología, Vulcanología, Hidrogeología y Meteorología de Guatemala and the Institute of Solid Earth of the University of Bergen, Norway. Numerical simulations were carried out in 2004 by the Central American Seismological Centre (CASC), the Centro de Published by Copernicus Publications on behalf of the European Geosciences Union

Objectives

Results

Conclusion