[SSS17-P13] Re-evaluation of the relation between various magnitude scales
Keywords:Magnitude, Moment magnitude(Mw), JMA magnitude(Mj)
Using bulletin of the International Seismological Centre(ISC), I studied relations among Mw and other magnitudes reported by several agencies(ISC, NEIC, JMA and NIED etc.) for earthquakes occurring in and around Japan and some other regions. The result of the study shows that Mws reported by different agency agree well with each other showing universality and robustness of Mw as a scale for earthquake size. Deviations of conventional magnitudes from Mw are generally similar to those reported by Utsu(1999). However, among conventional magnitudes, Mj (Tsuboi(1954), Katsumata(2004) ) shows minimum deviation from Mw within the range from Mw=4.0 to 7.0. Mj will be better substitute of Mw when it is not available. Several other interesting results are also to be presented.
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