Comparative Analysis of Past Earthquake Simulation and Test Operation

Abstract

The Korea Meteorological Administration (KMA) provides an earthquake early warning (EEW) service by issuing prompt earthquake information for the public to prepare for severe earthquakes. The KMA has established high-quality seismic stations to provide prompt and precise EEW service and has been monitoring observed seismic waves in real time. The ambient signal exhibits characteristics of small repeated amplitudes owing to the background noise near the seismic station. If seismic waves from earthquakes or explosions are observed in seismic stations, their detected amplitudes are higher than those of background noise and possess specific features. Thus, the methods for differentiating between the observed signal and any signal attributed to earthquakes or noise can be the starting of EEW and the main technique. Because this technique is based on the empirical relationship derived using postprocessed data or specific criteria as the standard, it can have more advantages for optimizing the criteria or standards through observing several seismic events in seismic stations operated in real time. However, fewer earthquakes have occurred in the Korean Peninsula compared to the West of the United States, Japan, and Taiwan. It is difficult to set up the optimal criteria and validate it for seismic stations operating in Korea. In this study, we applied simulated methods to validate the possibility of setting up the optimal criteria. For the simulated results, the analyzed data did not include any delayed waveforms under the ideal condition. We compared the analyzed results observed in detail during the EEW-testing periods. Even though differences between the simulation and EEW-testing results were observed, it was proven that there was no problem in analyzing the earthquake information. In addition, we could design the optimization of module for detecting the P-wave in the Korean Peninsula.