Statistical study on the regional characteristics of seismic activity in and around Japan: frequency-magnitude distribution and tidal correlation

Abstract We propose a statistical analysis method to identify common features of seismic activity that are indistinguishable from most other seismicity, and find anomalous differs these features. Using the hypocenter catalog earthquakes which occurs in around Japan during past 20 years, we apply this for parameters frequency-magnitude distribution parameter expresses correlation seismicity with tides as indices, focus on objectively understanding regional characteristics seismicity. As result, extracted "typical" probability density each index value regions "anomalous" index-value distributions differ significantly typical distributions. In terms distribution, estimated values indices areas can be explained variations corresponding effects fluids, interplate coupling, stress fields control faulting styles have been pointed out previous studies. By extracting depend earthquake occurrence interval were identified. Although showed no clear tides, tidal changes reflect proportion occurring series periods shorter than period; it is therefore useful an capture such intervals. also show represented by existing models or their extensions. using proposed reference, possible quantify degree anomaly same concept presented here; hence, should applicable monitor activity. Graphical