## 4 Summary--Conclusions
In the regions of Chania and Rethymno, the local faults appear to have a low angle, while at depths greater than 30 km, a low-angle surface is evident in the first 50 km of the cross-sections that were performed, possibly related to the top of the subducted lithosphere in the area. Some smaller concentrations of earthquakes were observed in two of the sections performed in sub-region 3, SW of Crete Island (Matala; Figure 11). The relocated hypocentres of these earthquakes were distributed from shallow depth down to about 25 km, possibly related to the Messara fault, and a more shallow one (<10 km) connected to the Matala aftershock sequence near the Sivas north-dipping normal fault. Further to the east, the geometry of the hypocentres as they appear in the performed cross-sections in Central Crete revealed the activation of some high-angle normal faults, dipping \(\sim\)80\({}^{\circ}\) to the W, in the 2021-2022 Arkalochori seismic sequence area. The cross-sections that cut the 2021-2022 Arkalochori aftershock sequence volume reveal two sub-vertical structures whose surface projection coincide with the Avli (\(\sim\)35 km in D-D\({}^{\prime}\)) and Kastelli (\(\sim\)45 km in D-D\({}^{\prime}\)) normal faults. Ref. [63] describes that during the main phase of this seismic sequence. Apparently, a large asperity of a west-dipping normal fault was broken and distributed stresses towards its northern and southern edges, triggering aftershocks mainly in two large groups, separated by a spatial gap, which could result in this complex image of epicentre distribution. In the region of Eastern Crete (sub-region 6), two smaller activated features were revealed in the area between Agios Nikolaos and Zakros, related to the N-S striking high-angle normal faults. Summarising, we can state that a new database of seismic events with well-constrained hypocentral parameters was compiled based on the newly formed local velocity models. The resulting models of the crust and upper mantle are comparable on a both local and regional scale with previous studies that used data from the seismic activity of the Southern Aegean and previous seismic surveys conducted in the region [1; 46; 48; 49; 53]. These 1 Dvelocity models aimed to improve the hypocentre locations of the available dataset. The regional distribution of seismic activity shows:  
* A complex shallow structure in Crete's central region mainly attributed to the dense pattern of neotectonic faults;
* A smoother and more continuous image in deeper slices (>40 km) where high V\({}_{\rm P}\)/V\({}_{\rm S}\) ratio (>1.82) distribution is observed. This process will provide a foundation for future studies on the Wadati-Benioff zone geometry in the Southern Aegean, as well as the identification of fault zones related to historical events with limited information and the properties (variation of thickness) of the seismogenic layer. The following supporting information can be downloaded at: [[https://www.mdpi.com/article/10.3390/app13179860/s1](https://www.mdpi.com/article/10.3390/app13179860/s1)]([https://www.mdpi.com/article/10.3390/app13179860/s1](https://www.mdpi.com/article/10.3390/app13179860/s1)), Figures S1-S12: Distribution of the seismic events using the final P-S velocity model in the sub-regions and plot of the absolute locations as a function of horizontal uncertainty or ERH (left) and vertical uncertainty or ERZ (right) as well as histograms of the error statistics between the initial (green) and the final 1D model (red) obtained in this study. Figure S13: (a) Location of the 2018-2023 catalogue for 5321 events, (b) relocated events using hypoDD. Figures S14-S18: Distribution of the located (left) and relocated events (right) that occurred between June 2018 and May 2023 in the selected areas. Conceptualisation, A.K. ; methodology, A.K. and F.V. ; software, A.K. ; validation, A.K. and F.V. ; formal analysis, A.K. and F.V. ; investigation, A.K. and F.V. ; resources, A.K. and F.V. ; data curation, A.K. and F.V. ; writing--original draft preparation, A.K.