Point of contact between archaeology and paleo-earthquake research.

Abstract

The Japanese Islands, which underwent significant crustal movements in recent times, have been inhabited over a long period of time. Therefore, abundant evidence of paleo-earthquakes is expected to exist on archaeological objects. The author presents examples of this evidence from three points of view, as follows.1) Deformation of tumuli: Kondayama and Hakuchohjinja tumuli, which had been constructed on an active fault, were displaced about 1.8m vertically by a historical earthquake. The earthquake is inferred to have occurred in the year 1510 and to have been of magnitude 7.1.2) Trace of paleo-earthquake discovered by archaeological excavation: Evidences of liquefaction were clearly observed at Kitogenishikaidoh, Hotarudani, and Kizugawakashoh Sites. The ages of the earthquakes which caused the liquefaction at these places were estimated by archaeological method.3) Submergence by paleo-earthquake: A fault scarp, formed by the earthquake that occurred in 1611, dammed up the rivers forming a small lake on the western fringe of the Aizu Basin. Some villages and roads had to be moved beyond the lake. Submergence by paleo-earthquake is similarly observed on the shores of Lake Suwa and Lake Biwa.