On the Cause of the Great Earthquake in 

 Central Japan, 1891. 



By 



B. Koto, Ph.D., Rigakuhakushi, 



Professor of Geology, Imperial University. 



With Plates XXVIII- XXXV. 



Introductory. 



Contents. — Introductory. I. Dislocations. II. Geology and Topography of Mino and 

 Owari. III. The Great Earthqviake of the Mino-Owari Plain. IV. Various Views as to 

 the Origin and Cause of the Earthquake. V. Relation of the Great Fault to the Kecent 

 Earthquake. VI. The Course of the Line of the Great Fault that caused the Earthquake. VII. 

 Concluding Remarks. 



Geologif^ts have rarely enjoyed ,so good nn opportunity as that 

 afforded them by the convulsion in the Mino-Owari plain, of observing 

 those great displacements of rocks called "y"«»/^.s," which may only be 

 brought about in the course of ages. Only a very few cases have ever 

 been recorded in the annals of earthquakes, of the formation of throws 

 of strata accompanied by subterranean shocks. 



Lyell mentions in his classical work, Frinciple.s of Geology, a case 

 that occurred in New Zealand, in 1855. A tremendous earthquake 

 was experienced there, by which, especially in the vicinity of Welling- 

 ton, in North Island, a tract of land comprising 4,600 square miles is 

 supposed to have been })ermanently iq3i-aised from 1 to 9 feet. The 

 line of fault was distinctly observed in the sea-cliff, called Muka-Muka, 

 where the uplifted older rocks abut upon the lower. Tertiary plain 

 of Wairarapa; and the C(3urse of the fault was traceable inland 

 to the extniordinary distance of nl:)out 90 miles, in approximate! v 



