UNESCO-IOC Meeting of Experts on tsunami sources and hazard in southern Peru and northern Chile

Résumé

The Pacific coast of South America experiences regular moderate and major earthquakes and associated tsunamis. The significant seismic activity in this region is due to the subduction of the Nazca plate under the South American plate along the Perú-Chile trench, located between 90 and 160 km offshore the Peruvian and Chilean coast. The Nazca plate subducts beneath the South American plate at an average rate approximately of 6.5cm/year, one of the fastest subduction rates in the world (Norabuena et al., 1998; Sladen et al., 2010; Altamimi et al., 2017; Jarrin et al., 2023).

A very large tsunami associated with the Perú-Chile trench has the potential to cause widespread loss of life, damage, and disruption to the region. Similarly, smaller events could potentially generate locally devastating tsunamis. Along the border region of Chile and Perú, there are important human coastal settlements with an increasing dependency on coastal-based tourism. Moreover, the population and key economic infrastructure—associated with important inland mining-based economies—are concentrated in coastal low-lying areas.

This proposed meeting of experts will focus on the uncertainties of tsunami hazard in the Chile-Perú border region and identify possible tsunami sources. Its objective is to identify and quantify credible tsunami sources along the Perú-Chile subduction zone that could significantly impact the local and regional area. Distant generated tsunamis affecting the region may also be discussed. Expert consensus in the characterization of regional tsunami sources will be reflected in a Meeting Report to be published by UNESCO and source parametrization will be tabulated and added to several international databases for use by the Pacific community.