Permalink : http://hdl.handle.net/2115/38166

JaLCDOI : 10.14943/gbhu.72.373

The Kurile Islands earthquakes of November 15, 2006 and January 13, 2007 are studied by using the volumetric strainmeter array in Tokai-Kanto area, Japan. The first-motion of long-period P waves recorded by the array shows good correlation with the first-arrival of tsunami waves observed on the Pacific side of Japan. The amplitude ratio of the long-period P waves (T > 50 s) between the two earthquakes explains the difference in moment magnitudes. The inconsistency between moment magnitudes and JMA magnitudes of the two earthquakes may have been caused by the difference of phases and period ranges used in the determination of the two magnitudes.