古記録による歴史的大地震の調査（第一報）（弘化四年三月二十四日善光寺地震）

Abstract

When a big earthquake occurs, the en quete method through post cards is usually carried out for the inverstigation of intensity distribution and damage and their relations to the ground conditions and geology. Thus collected data isalsousefulforthe prevention of damage due to big earthquakes. This method can be applied to large historical earthquakes when abundant historical documents are found. As the first step of the application of on qttete method to historical earthquakes, the Zenkoji earthquake which occurred at about 10 p.m. on the 24th of March, 1847 was studied