Evidences of Paleoearthquakes Found out in some Archaeological Sites

Abstract

Numerous evidences of paleoearthquakes have been discovered in many archaeological sites. The present writer has investigated on these evidences and comes to the following conclusions;
1) Some traces of the Paleo-Nankai and Tokai earthquakes were found mainly along the Southwestern Pacific coast. The present writer infers from these archaeological evidences and old documents that these great earthquakes occurred simultaneously in the years A. D. 1498 and A. D. 684.
2) The ages of the faultings which caused big earthquakes, were revealed in some regions. For instance, the fault movement along the northern rim of the Osaka Plain is proved to have occurred in the years A. D. 1596 and about A. D. 500.
3) Traces of sand eruption were found out in many sites. Some important behaviors of sand layers, caused by a liquefaction, were observed in these traces.