Elenora VAN RIJSINGEN (ENS de Paris)



Unraveling the seismotectonics of the Lesser Antilles subduction using geodetic observations

The Lesser Antilles subduction zone, forming the eastern boundary of the Caribbean plate, is a region with a complex tectonic history and a seismogenic behaviour that has puzzled scientists for decades. It has been seismically quiet over the past 100 years, with no large thrust events being recorded along the subduction megathrust. However, two large historical earthquakes occurred in the 19th century and have been interpreted as thrust events, although direct evidence is missing. This raises questions about the seismogenic behaviour of the region, and whether we should expect large megathrust earthquakes to occur in the future or not. I will present you our recent work where we explore the seismogenic behaviour of the Lesser Antilles using geodetic observations. We use a Bayesian approach to infer the interseismic coupling from horizontal GNSS velocities, and compare current vertical velocities with estimates from paleo-geodesy to understand the region's long-term seismic character.