###### Abstract
It is worth noting that the earthquake did not induce direct expression of primary surface faulting [23]. Furthermore, the onshore part of the WAFZ has no direct surficial morphotectonic or geological evidence onshore of the Western Peloponnese. On the contrary, its offshore extension is linked with an offshore pull-apart basin NE of the Strofades Islets [24,25]. The part of the Ionian Sea located south of Zakynthos constitutes a downthrown block of the External Hellenides at the northern end of the Hellenic Trench. Flat thrusts, strike-slip and normal faults are detected [25], with thrusting prevailing over strike-slip or normal faulting [7,26]. The prominent feature of this area is a 46 km-long, NW-SE-trending thrust system [27], responsible for the generation of the 1997 Mw6.6 [28] and the 26 October 2018 Mw6.7 [29] Zakynthos earthquakes. The intense seismicity on the southern part of the Ionian Sea is attributed to the proximity of this area to the CLTFZ, the Hellenic Trench and many onshore faults in the South Ionian Islands. These islands have been formed either on the margins or within fault blocks. At Lefkada Island, typical cases are the fault zones in the western coastal part [15], along which extensive environmental effects were generated from the two strong Lefkada earthquakes on 14 August 2003 (Mw6.3) [30,31] and on 17 November 2015 (Mw6.4) [32], triggering many rockfalls and landslides in the western coastal part of the island [17,33]. In Cephalonia, several active faulting zones at the northern, western and southwestern parts of the island are susceptible to triggering of earthquake environmental effects, with the most typical example being the numerous rockfalls and slides due to the August 1953 earthquakes [34]. In Zakynthos, typical cases of active faults are the Volimes fault zone in the north part of the island, which has been formed in the transition from the Northern Zakynthos fault block to the Central Zakynthos one. Similar active faults are also located at the eastern and southern parts of Zakynthos Island [16]. Regarding the North Ionian Islands, a NNW-SSE-trending system, with a relatively extended shelf width represents the convergence (continental collision) between the Apulian Platform and the Hellenic foreland, with Corfu lying on the northwestern edge of the Hellenic Fold and Thrust Belt. The E-W-striking Southern Salerno-North Corfu fault zone is a major right-lateral structure that crosses Corfu from coast to coast [35] and which has resulted in the displacement of N-S-trending fold axes and thrusts [36]. This part of the Ionian Sea is characterized by lower seismicity than the southern one. The North Ionian Islands have suffered damage from earthquakes generated in adjacent areas, such as the 20 February 1743 Salento peninsula (Apulia, southern Italy) earthquake with Mw7.1 and I\({}_{0}\) = IX, which triggered landslides in Corfu [37] and severe structural damage, including building collapses in Corfu town [38], attributed to very efficient strong propagation with NW-SE preferential directivity [39]. The complex geotectonic status of the area resulted in the high seismic activity that occurs in the broad Ionian area. However, during the last decade, and mainly during the period between 2014 and 2018, increased seismicity was observed, and strong events (\(M>6.0\)) shocked the central Ionian Islands. Early 2014, two earthquakes (Mw5.9 and Mw6.1) occurred on Cephalonia Island, while in November 2015 and in October 2018 two earthquakes of Mw6.4 and Mw6.7 took place at South Lefkada and offshore south of Zakynthos, respectively. The regional crustal motion along the entire Ionian Sea and western Greece, as well as the local deformation on the central Ionian Islands, have been studied and monitored with local dense Global Positioning System (GPS) networks [13,40,41] and continuous Global Navigation Satellite System (GNSS) stations [42,43].