In Japan, for shallow (depth < 60 km) earthquakes within 600 km, the Japanese Meteorological Agency calculates[2] a magnitude labeled MJMA, MJMA, or MJ. (These should not be confused with moment magnitudes JMA calculates, which are labeled Mw(JMA) or M(JMA), nor with the Shindo intensity scale.) JMA magnitudes are based (as typical with local scales) on the maximum amplitude of the ground motion; they agree "rather well"[3] with the seismic moment magnitude Mw in the range of 4.5 to 7.5,[4] but underestimate larger magnitudes.
Katsumata, A. (June 1996), "Comparison of magnitudes estimated by the Japan Meteorological Agency with moment magnitudes for intermediate and deep earthquakes.", Bulletin of the Seismological Society of America, 86 (3): 832–842, Bibcode:1996BuSSA..86..832K, doi:10.1785/BSSA0860030832, S2CID130279928.