The 30 October 2020 Aegean Sea Tsunami: Post-Event Field Survey Along Turkish Coast

On 30 October 2020, a strong normal-faulting earthquake struck Samos Island in Greece and İzmir Province in Turkey, both in the eastern Aegean Sea. The earthquake generated a tsunami that hit the coasts of Samos Island, Greece and İzmir, Turkey. National teams performed two post-tsunami field surveys on 31 October to 1 November 2020, and 4-6 November 2020, along the Turkish coastline; while the former was a quick survey on the days following the tsunami, the latter involved more detailed measurement and investigation focusing on a ~ 110-km-long coastline extending from Alaçatı (Çeşme District of İzmir) to Gümüldür (Menderes District of İzmir). The survey teams measured runup and tsunami heights, flow depths, and inundation distances at more than 120 points at eight different localities. The largest tsunami runup among the surveyed locations was measured as 3.8 m in Akarca at a distance of 91 m from the shoreline. The maximum tsunami height of 2.3 m (with a flow depth of 1.4 m) was observed at Kaleiçi region in Sığacık, where the most severe tsunami damage was observed. There, the maximum runup height was measured as 1.9 m at the northeastern side of the bay. The survey team also investigated tsunami damage to coastal structures, noticing a gradual decrease in the impact from Gümüldür to further southeast. The findings of this field survey provide insights into the coastal impact of local tsunamis in the Aegean Sea.