Research on the Magnitudes Determined by the Substations of Shaanxi Digital Seismic Network

On the Basis of 1998-2003 digital seismic data from the Shaanxi Digital Seismic Network, we analyzed the magnitudes determined by the substations of the network. The result shows that if taking average network magnitude as a standard magnitude, the magnitude deviation would have a regional distribution. For the substation located at the plain-mountain boundaries, the observed magnitude will be bigger than standard magnitude when the shock occurs in the mountain, but smaller when it occurs in the plain. We discussed the reason for magnitude deviation in the end of the paper.