The Archaean Formation 



of the 



Abukuma Plateau. 



By 



B. Koto, Ph. D., Ri^akuhakiishi. 

 Professor of Geology, Science College, Imperial University 



TI'(7/( Plates XXn-XXVII. 



I. Introduction. 



T)r. Ediiiüiid Xniiinniiii, in his excellent little work Ucher den 

 Ban und die Ivntslelntntj der jtijxiN/scJien Inseln^ luis proposed a priinnrv 

 division of all Japan irito Xortlunai and Southern, by a remarkable, 

 great, o'eotect(^nic line, a " fos.'^ei maijna^^^ which, as he savs, traverses 

 tlie \vh(3le breadth ofthe ]\[ain Isl.and, froin the Tacific Ocean to the 

 Ja])an Sea. 



In spite (^f a controversy that has arisen between Dr. Xanniann 

 and T)r. Ilarada, as to the existence or non-existence of that geolouac 

 moat, it must nevertheless be admitted that that division is in e\ery 

 way a most satisfactory one. The South was the cradle of our 

 civilization, while the Xorth was, down to the middle a<i"es, tlie home 

 of tlie Ainos. The climate of the St^uth is sunny and mild, iH'inu' 

 influenced 1)y tlie warm, genial Ivuro-shiwo that washes the Paeitie 

 coast ; while the Xorth is chilly, for the ])olar cairrent runs close 

 bv^ tlu' shore. 



