AFTER-SUOCKs; AND SI'.\( F.-1>IST111BÜTI0X OF SfJISMIC WAAKS. 1!> 



The Mino-Owari cartliquiike gives u concrete instance wliicli 

 explain^? this phenomenon also. From B. Koto's'-' valuable paper 

 we may cite the geology of the domain. 



The extensive and populous plain of ^Nlino and (^wari is on 

 three sides bounded by mountains mainly of PaLneozoic formation. 

 Granite and schistose rocks make up the main blocks of the 

 range. Beyond the mountain-ridge, in the north, lies a plain 

 of considerable extent, where the Mesozoic forniation is extensively 

 developed, and later on has been intruded into in places by 

 Tuasses of Tertiary eruptions. The city of Fukui lies in the basin 

 of the River Kudzuryu draining this plain. 



Similarly, in the west, there lies a plain of recent geological 

 era at the eastern border of Lake Biwa, the city of Hikoue being 

 the most populous one in the region. It was very remarkable 

 that these two regions were severely shaken and greatly damaged 

 by the earthquake, whereas the stretches of land Ijetween these 

 and the Mino-Owari plain suffered very little. 



Under the point of view in question, it means simply that 

 the Pakeozoic rocks, having less hysteresis, conducted the seismic 

 wave very well 1)ut were not damaged by virtue of their high 

 elasticity, while the Cainozoic rocks in contact with them, wholly 

 absorbing the seismic energy, were severely shaken in consequence 

 of their inferior elasticity and large hysteresis. 



In conclusion, I wish to express my best thanks to Prof. H. 

 Nagaoka for his kind guidance throughout the whole of this 

 investigation. 



* B. Koto. Loc. cit. Geology .and Topography of Mino :uk1 Ow.irL 



