Current deformation in Hispaniola observed from InSAR–derived surface velocities

The oblique convergence between the Caribbean and North American plates is accommodated, in Hispaniola, by left-lateral strike-slip on two major sinistral fault systems and by intra-arc shortening. We apply a Persistent Scatterer Interferometry (PSInSAR) approach to Sentinel-1 data using six tracks acquired between 2016 and 2023 to generate time series of interseismic velocities over the entire island. We merge the resulting ascending and descending tracks with GNSS–derived velocities to determine a spatially-continuous 3D velocity field that documents deformation gradients across large fault systems. The Enriquillo–Plantain Garden fault fits a single locked–fault model, while the Septentrional one potentially involves several sub–faults. Strain in southeastern Haiti and the southwestern Dominican Republic is well modeled by the Jérémie-Malpasse-Bahoruco oblique reverse fault-system, which represents a significant, but overlooked, regional hazard source.