Traces of Paleo-tsunamis Occurring during the Last 6500 years

Abstract

 View of tsunami deposit outcrop at Jyuosaki, Noda Village, Iwate Prefecture, Japan. Photo at the upper left is the cover photo of Part I, taken by a drone from offshore (white circle in the photo indicates the location of the outcrop in the middle photo). The photo at the right is a close-up view of the trench indicated by the arrow in the middle photo, where several tsunami deposits can be identified; the sand layer below the To-a Formation (Towada a tephra, A.D. 915) is presumed to be the Jogan tsunami deposit (A.D. 869). Traces of paleo-tsunamis occurring during the last 6500 years can be observed in the whole outcrop, which is over 7 m in height.

(Photograph & Explanation: Noriyoshi TSUCHIYA and Kengo NAKAMURA)