CALCULATING FOCAL DEPTH USING TRAVEL TIME DIFFERENCE OF SPN AND PN PHASE

Focal depth is an important parameter of earthquake location.Using travel time difference of sPn and Pn phase,we calculated focal depths of four local earthquakes occurred in the crust recorded by Shenyang seismic station and compared it with the results given by National and Liaoning Seismograph Network.The results indicate that about 75 percent of the focal depth calculated by Shenyang station is consistent with the National results and exactly consistent with the Liaoning Seismograph Network.