Earthquake early warning system in Liaoning, China based on PRESTo

Liaoning is located in northeast China with a high level of seismic activity, and earthquake early warning is important for the mitigation of seismic hazard. In this work, we implement PRESTo, an open-source software platform for earthquake early warning based on regional seismic records, to the Liaoning seismic network. For the early warning of earthquakes in Liaoning, a travel-time table is created for event detection and location using an average crustal model, and the empirical relation is established between the earthquake magnitude and the initial P-wave amplitudes. Using archived seismic records of past earthquakes, we determine the optimal values for Liaoning using the core algorithms of PRESTo. Based on the optimal parameters, the uncertainty in event location is generally less than 5 km, and the lead time of the early warning is ~15 s at 100-km epicentral distance. The implemented system can be directly put into routine earthquake early warning operation by linking it with the real-time data stream from the Liaoning seismic network.