Earthquake archaeology in Japan: An overview
Earthquake archaeology developed in Japan simultaneously with that in the Mediterranean in the mid-1980s. By 1996, evidence of earthquake occurrence had been documented at 378 sites throughout the archipelago. The main features identified include various results of liquefaction, faults, landslips, and surface cracking. This evidence differs greatly from the standard Mediterranean focus on building damage, and the reasons for the very different natures of archaeoseismology in these world regions are explained herein. This article recounts the development of this new subfield, inspired by the interest of geomorphologist Sangawa Akira and taken to its most recent advances in identifying soft-sediment deformation structures by geoarchaeologist Matsuda Jun-ichirō. The evidence of earthquake activity at archaeological sites can be matched with earthquakes caused by either active fault movement or subduction. The historical record of earthquake occurrence, already documented back to 599 C.E., is extended into the prehistorical record through relative dating of artifacts and features on archaeological sites. Both the identification and the dating of the archaeological evidence of earthquakes can be challenged, though the “territorial approach” gives the data a significance that is not achieved through analysis of single sites.