Tsunami modeling and inundation maps of the ∼M8.6, 1787 earthquake along the Oaxacan coast

Abstract

The March 28, 1787 (M∼8.6) earthquake on the Pacific coast, was the biggest known in Mexico. There are testimonies of damage caused by the tsunami waves at several different points along the southwest coast. Even though there have been several tsunamis known to have impacted this region, there are scarce tsunami observations. In this study, we generate a suite of 350 potential ruptures that we explore as candidates for the 1787 San Sixto earthquake. We focus this study in three coastal areas: Salina Cruz, Huatulco and the Mazunte-Puerto Ángel segment of the Oaxacan coast. We will discuss results of the homogeneous and heterogeneous slip models as input for tsunami simulations. The results obtained for every particular town and possible tsunami effects such as resonance, wave energy focusing and prone inundation areas are discussed. The scope of this work is to greatly expand on previous tsunami modeling efforts as an important tool for studies of tsunami hazards for future events in order to increase resilience in coastal populations.