Table 1 Validation criteria for the historical tsunami heights (before the 1960 Chilean earthquake tsunami) (Japan Society of Civil Engineers 2002)

A

Validity is high. Both the tsunami run-up and its location are confirmed by a historical document, and the height has been measured in recent years

B

Validity is moderate. Both the tsunami run-up and its location are confirmed by a historical document, although the height has not been measured in recent years

C

Validity is low. The tsunami run-up is confirmed by a historical document or tradition, although its location is indicated only by a village name, and a detailed location is unclear

D

Validity is doubtful. The tsunami run-up is estimated by conjecture through the extent of damage and its associated phenomena