DETERMINATION OF FOCAL DEPTH OF MADUO MS7.4 EARTHQUAKE BY TELESEISMIC DEPTH PHASE pP
For the determination of the focal depth of moderately strong earthquakes,the teleseismic converted wave depth phase pP and sP sounding is an effective method,and the depth accuracy can reach 2 km when the depth phase is clear.Teleseis program is used to fit the theoretical seismogram of the Maduo MS7.4 earthquake,and compared with the actual observation.The focal depth of the earthquake is measured,and the influence of the crustal velocity model on the teleseismic body wave depth phase pP sounding is analyzed and discussed.The results show that the initial rupture depth of the Maduo earthquake is 12 km,and the uncertainty of the VP in the velocity model has a greater in-fluence on the arrival time of the seismic phase in the theoretical seismogram.