陕西数字地震台网子台测定震级的研究

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

使用陕西数字地震台网1998～2003年间的地震记录,以台网平均震级为标准震级,分析了各子台的测定震级。结果表明,各子台测定震级的偏差存在地域分布特征,震级随方位角显示趋势性变化。台址位于平原和山区交界处的台站,对于山区发生的地震测定震级偏大,对于平原地区发生的地震测定震级偏小。最后对震级偏差成因进行了探讨。

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.