Importance of Velocity Model to Accurate Location of earthquake

How to get the appropriate crustal velocity model is a classical problem in seismology research. And the accurate determination of the epicenter and the focal depth is closely related to the velocity model. This paper briefly introduces the present situation of the velocity model of the seismic network in China, and selects earthquakes took place in Fujian and Inner Mongolia as examples to explain the importance of the appropriate velocity model for the accurate determination of earthquakes.