Search

In this study, we used pattern informatics (PI) to visualize patterns in seismic migration for two large earthquakes in Taiwan. The 2D PI migration maps were constructed from the slope values of temporal variations of the distances between the sites and hotspot recognized from the PI map. We investigated the 2D PI migration pattern of the 1999 Chi-Chi and 2006 Pingtung earthquakes which originated from two types of seismotectonic setting. Our results show that the PI hotspots migrate toward the hypocenter only when the PI hotspots are generated from specific depth range which is associated with the seismotectonic setting. Therefore, we conclude that the spatiotemporal distribution of events prior to an impending earthquake is significantly affected by tectonics. [ABSTRACT FROM AUTHOR]

We report the retrospective analyses of frequency-magnitude distributions (FMD) and pattern informatics (PI) for the Pingtung offshore doublet earthquakes having magnitudes 6.7 and 6.4. The frequency-magnitude distributions of earthquakes that occurred in the study area preceding the Pingtung doublets demonstrate the activation of moderate events since March 2004, about three years before the Pingtung doublets. In addition, in the calculated PI map, the hypocentral area of the doublets exhibits the signatures of anomalous activity associated with the precursory seismic activation. Our study therefore suggests that, by inspecting temporal variations in the frequency-magnitude distributions of earthquakes, together with the hotspot locations with intense seismicity changes in the PI map, it is possible to shed light on the relevant preparation processes of the forthcoming large earthquakes. [ABSTRACT FROM AUTHOR]