An automatic monitoring system for nonvolcanic tremors in southwest Japan

摘要: [1] The recent development of a system for exchanging and distributing seismic waveform data over high-speed networks enables events to be monitored in real time throughout Japan. In the present study, we have developed an automatic real-time monitoring deep nonvolcanic tremors southwest The automatically detects occurrence determines their hypocenters time. addition, creates image files detected tremor activities makes them accessible via World Wide Web. To detect carry out two-step numerical hypothesis test, which first step is test whether two given envelope seismograms are correlated second event occurs using results test. This applied every 2 min. Once detected, can regard lags that generate maximum cross correlations as travel differences, use hypocenter determination. Although this procedure nontremor signals, most rejected several criteria. Since start 2006, has worked well detecting wide variety activities. Results from will contribute understanding stress relaxation process transition zone between locked stable slip zones subducting Philippine Sea plate interface.