Simulation of the 2004 tsunami of Les Saintes in Guadeloupe (Lesser Antilles) using new source constraints

Abstract

The arc of the Lesser Antilles is associated with a significant tectonic activity due to the subduction of the Atlantic oceanic plate under the Caribbean plate. Earthquakes in this context have the potential to trigger landslides and tsunamis due to the important vertical seafloor displacement. The historical tsunamigenic earthquakes in this region are rare, but the damages they may have generated before along the coasts show that they pose a considerable threat to the closest inhabited islands. The most recent tsunamigenic earthquake occurred in 2004 in the area of Les Saintes, along a normal fault system located in the back-arc of the subduction. This M w = 6.3 earthquake generated small waves with 2 m of run-up in several bays of Les Saintes, a group of islands in the South of Guadeloupe. A recent survey conducted in the source area using deep-sea vehicles revealed for the first time an important coseismic slip on the Roseau fault plane, attributed to the 2004 event, which had not been predicted in the seismic inversion models. This event and the dataset on the Roseau fault gives the opportunity to model precisely the earthquake, to compare the simulation results with the observations and to evaluate the impact of the rupture heterogeneity and rupture shallowness on the height of the tsunami waves. Extending our earlier work (

The July 20, 2017 Mw = 6.6 Bodrum-Kos Earthquake, Southeast Aegean Sea: Contribution of the Tsunami Modeling to the Assessment of the Fault Parameters

“…Several sensitivity studies show that a uniform rupture and a more complex one give back very close results of simulation in terms of water-heights and water-heights distribution (An et al, 2018;Li et al, 2016). Other studies show that increasing the rupture complexity of source with a fixed magnitude will also increase the amplitude of the tsunami locally (Cordrie et al, 2020;Geist, 2002;Mueller et al, 2015) but does not seem to affect the geometry of the water-height distributions in the far field. In this study, we discriminate the models mostly using the geometry of the water-height distribution and the shape of the waves that should not be strongly impacted by the slip heterogeneity.…”

How Would the Potential Collapse of the Cumbre Vieja Volcano in La Palma Canary Islands Impact the Guadeloupe Islands? Insights into the Consequences of Climate Change

“…In the Caribbean, islands populations are particularly exposed to tsunamis hazards and significant efforts have been made in recent decades to identify potential sources since the presence of subduction zones near the Lesser Antilles creates a high potential of tsunami hazard [3][4][5][6]. As part of the C3AF project (Consequences of Climate Change in the French Antilles) several scenarios of potential tsunamis have been simulated to develop tsunami inundation maps for the Guadeloupe archipelago.…”