Spatiotemporal Properties of Seismicity and Variations of Shear-Wave Splitting Parameters in the Western Gulf of Corinth (Greece)

The Western Gulf of Corinth (WGoC) exhibits significant seismicity patterns, combining intense microseismic background activity with both seismic swarms and short-lived aftershock sequences. Herein, we present a catalogue ~9000 events, derived by manual analysis double-difference relocation, for the WGoC during 2013–2014. high spatial resolution hypocentral distribution permitted delineation activated structures their relation to major mapped faults on surface. spatiotemporal revealed 32-km-long earthquake migration pattern, related pore-pressure diffusion, triggering moderate mainshock-aftershock sequences, as fluids propagated eastwards in course ~15 months. anisotropic properties upper crust were examined through automatic shear-wave splitting (SWS) analysis, over 2000 SWS measurements at local stations. An average fast polarization direction N98.8°E ± 2.8° was determined, consistent maximum horizontal regional stress. Temporal variations normalized time-delays between slow shear-waves imply alterations level stress or microcrack fluid saturation long-lasting diffusion episode, particularly before events. study provides novel insights regarding active fault structures, mechanisms WGoC.