Spatial Distribution Characteristic of Archaeological Ruins with Land Liquefaction Vestiges Analyzed by GIS

Land liquefaction triggered by huge earthquake occurs repeatedly at the same area (Wakamatsu, et.al., 2006). Therefore, it is important to grasp the land liquefaction occurrence area in the past for taking measures against land liquefaction disaster. (Wakamatsu, 2011) produces the map data for historic liquefaction sites in Japan based on recent field survey and historical document from the 8th century to 2008. Also, though (Relief Liaison Conference of Archaeological Artifacts and Archaeological Artifacts Research Society, 1996) completed information on land liquefaction vestiges found on archaeological ruins in Japan at that time, later information on land liquefaction vestiges isn't made into database, except for Kanto district, Japan. Therefore, we created a geographic information system (GIS) dataset about information on archaeological ruins with land liquefaction vestiges in Niigata Prefecture, Japan, and analyzed a characteristic of spatial distribution of the ruins by associating with landform classification and/or distance from river by GIS. The result of this analysis indicated a clear trend, and it has great significance because the distribution tendency of land liquefaction in ancient period, which is not included in the "Maps for historic liquefaction sites in Japan", was comprehended.