DE I- 'EL OF MEN I ' OF SEISAR )L OG V FV J A PAN 281 



On the occasion of the recent earthquakes of Kwanto'^-* and Tazima/-^ 

 a number of papers appeared to which we are unable to refer in this 

 limited space. 



Tlie mutual i)hysical connexion between the different fault lines, 

 their relations to the geological or topographical structure, etc., have 

 been extensively investigated. The recent results obtained by Yamasaki 

 and Ogawa already cited are most noteworthy from the seismological 

 and geophysical points of view, as they afford some tangible basis for 

 any theory or speculation by theoreticians. 



Earth fissures observed after the Kwanto Earthquake have been 

 pursued and closely investigated by H. Obata.^^^ 



Discussions have often been as to the significance of the fault 

 lines appearing on the occasions of earthquakes, whether they are the 

 immediate causes of earthquakes or merely secondary phenomena 

 brought about as the eflects of the disturbance. In this cormection, 

 the discussions^''' on the causes of Kwanto Earthquakes by Ogawa, 

 Matsuyama, Terada, Fujiwhara, and others may be referred to. 



The systematic levelling works carried out by the Military Land 

 Survey, with the collaboration of the Japanese Members of the Inter- 

 national Geodetic Commission have rendered invaluable services to 

 seismology, by ascertaining the vertical displacements of bench-marks 

 after destructive earthquakes. Not to mention the case of the Mino- 

 Owari Earthquake which is perhaps known the wide world over, 

 the contributions to our knowledge made by the survey on the 

 occasion of the Sakurazima eruption,^^^ the Omati Earthquake,^**^ the 

 Simabara Earthquake^'' and the recent great earthquake^®' were and 



(1) Iraaraura, Yamasaki, Koto, Inouye, Suzuki, Nakamura, Omura, Uchida and 

 Terada, Ho., lOOA and B. Ogawa, Chikyu, 1 (1924), 1, 113, 199, 287. 



(2) Imaraura, Geogr. Rev. 1 (1925), 511. Yamasaki, Geogr. Eev., 1 1925), 517. 

 Suda, a Eeport issued by Imp. Mar. Obs. (1925). Saem. Nakamura, Saito Hoonkwai 

 Gakuzyutu Kenkyii Hokoku, No. 1 (1925). S. Ishikawa, J. Makiyama, F. Plomma, 

 Y. Karaikawa, etc., Chikyu, 4 (1925), 1. N. Kuma-ai, Chikyu, 4 (1925), 181. M. 

 Funakoshi, Chikyu, 5 (1926), 120. 



(3) H. Obata, Ho., lOOB (1925). 



(4) To be quoted later. 



(5) Oraori, Bull., 8, No. 1-6 (1914-22). A pamphlet issued by Mil. L- Surv. (1915). 



(6) Omori, Ho., 94 (1921); 98 (1922); Bull., 10, No. 1 (1922). 



(7) A. Iraamura, Ho. 99 (1925). The result of the survey after the Miyosi 

 Earthquake is yet unpublished. 



(8) H. Omura, IIo. iOOB (1925); besides some pamphlets, partly unpublished. 

 A map showing tiie depression and upheaval according to the results of the re-exami- 

 nation up to Oct., 1925, was recently completed- A depression of 1.6 ni at Tanzawa 

 district and an elevation of over 1.6 jn in Awa and sontliern Kadusa are shown. 



