Slow Slip Triggers the 2018 M _w 6.9 Zakynthos Earthquake Within the Weakly Locked Hellenic Subduction System, Greece

Slow slip events (SSEs) at subduction zones can precede large-magnitude earthquakes and may serve as precursor indicators, but the triggering of by slow remains insufficiently understood. Here, we combine geodetic, Coulomb wedge failure-stress models with seismological data to explore potential causal relationship between two SSEs 2018 Mw 6.9 Zakynthos Earthquake within Hellenic Subduction System. We show that both released up 10 mm aseismic on plate-interface were accompanied an increase in upper-plate seismicity rate. While first SSE late 2014 generated only mild failure stress changes (≤3 kPa), nevertheless sufficient destabilize faults various kinematics overriding plate, second caused 25 kPa prior mainshock. Collectively, these affected a highly overpressured mechanically weak forearc, whose state fluctuated horizontal deviatoric compression tension during years preceding Earthquake. conclude this configuration facilitated episodes seismic deformation ultimately triggered