Fig. 1

a Index map of Japan. b Map of eastern Mie Prefecture showing the study site. c Location of the “Lake Kogare-ike” study site on the eastern shore of Kamizaki Bay. d Ages and estimated rupture zones of historical tsunamis along the Nankai Trough (modified from The Headquarters for Earthquake Research Promotion 2013). Red solid lines, red dotted lines, and gray dotted lines represent certain, probable, and possible rupture zones, respectively. The 1605 Keicho earthquake (dotted blue line) is regarded as a tsunami earthquake or an earthquake off an adjacent trench (Yamamoto and Hagiwara 1995; Seno 2002; Ishibashi and Harada 2013; Tsuji 2016). Generic Mapping Tools (Wessel et al. 2013) was partly used to create Fig. 1d. e Sediment sampling locations and topographic setting of the study site. The photograph was captured by an unmanned aerial vehicle. f Aerial photograph of the study site showing the survey transect from the shoreline (point A) to the inland end of Lake Kogare-ike (point G). The photograph was taken by the Geospatial Authority of Japan on 24 September 2008 (photograph number: CKK-2008-1X-C13A-13). g Topographic profile from the shoreline to the study site. Elevations are expressed with respect to mean sea level at Tokyo Bay (Tokyo Peil, T.P.)