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

Abstract

On 30 October 2020, a strong normal-faulting earthquake struck Samos Island in Greece and Izmir Province in Turkey, both in the eastern Aegean Sea. The earthquake generated a tsunami that hit the coasts of Samos Island, Greece and Izmir, 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 similar to 110-km-long coastline extending from Alacati (cesme District of Izmir) to Gumuldur (Menderes District of Izmir). 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 Kaleici region in Sigacik, 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 Gumuldur to further southeast. The findings of this field survey provide insights into the coastal impact of local tsunamis in the Aegean Sea.