Reconciling fault growth histories in time and space and seismic hazard analysis: Western Gulf of Corinth

Understanding and monitoring active faults provides useful information in understanding fault movement and constraining seismic hazards. Recently,
short-term deformation rates have been increasingly studied and can be compared with long-term geological data. This study utilises Interferometric Synthetic Aperture Radar (InSAR) data from the European Ground Motion Service (EGMS) spanning 2018 to 2023 to investigate vertical ground deformation rates along the Psathopyrgos and Rion-Patras faults in the Gulf of Corinth, Greece. These two faults represent some of the most active zones of deformation in the region. Our observations reveal a consistent vertical deformation signal, which when combined with topographic data from a 5 m Digital Elevation Model (DEM), helps to constrain the spatial extent of tectonic deformation. We hypothesise that the current deformation across these faults is primarily driven by aseismic creep and interseismic deformation, which is picked up by the EGMS. With increasing microseismicity and possible seismic risk in the area, we perform a seismic hazard analysis to evaluate the potential impact of linked fault ruptures, particularly concerning densely populated areas such as the city of Patras. We obtain Peak Ground Acceleration (PGA) values of 414 − 432 cm/s² near the city of Patras and Rio. This research highlights the importance of integrating remote sensing data with geological and seismic observations to improve our understanding of fault behaviour and regional seismic risks.