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Official Journal of the Asia Oceania Geosciences Society (AOGS)

Fig. 6 | Geoscience Letters

Fig. 6

From: A short history of Japanese historical seismology: past and the present

Fig. 6

Examples of distributions of seismic intensities for various types and depths of earthquakes of the similar magnitudes. a Example of the interplate shallow earthquake (2005 Aug 16 M7.2). b Example of the intraplate intermediate depth earthquake (2003 May 26 M7.1). c Example of the very shallow earthquake (2008 June 14 M7.2). The area size of JMA intensity 5-upper and larger in a is almost equal to that of c, while that of b is far larger, although the magnitude of the event of b is the smallest. In a and b, the areas of JMA intensity 3 and larger extend to trench-parallel direction (the vertical direction of the figure), since the high-frequency waves have propagated through the slab. Although intensities in sites close to the source area are the highest in c, areas of the lower intensities were smaller than those of a and b. The area of intensity 2 of a in the southwestern part of Japan is the largest. All of these features reflect the difference in the amount of stress drop depending on the seismic source type, the difference in the structure that seismic waves have propagated, and the difference in the rate of change in hypocentral distances on the ground surface due to the depth of the source

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