基于中国地震台网观测报告的M_L与M_S经验关系

The empirical relation between M_L and M_S based on bulletin of seismological observations of Chinese stations

根据1990～2000年《中国地震年报》和2001～2008年《中国数字地震台网观测报告》的大量数据,研究了测定面波震级MS与近震震级ML的不确定性;采用双随机变量的回归方法,用3种不同的数据组,获得二者之间的3组新的转换关系。结果表明,自20世纪70年代使用至今的公式MS=1.13ML-1.08严重偏离数据组,已不适用于新的数据。考虑到测定震级的不确定性及数据的离散性较大等因素,认为采用关系式MS=0.03+0.98ML作为新的经验关系更合理适用。

Based on the data of Annual Report of China Earthquake between 1990 and 2000 and the Reports of China National Digital Seismic Network between 2001 and 2008,it studies the uncertainty of the determination of surface wave magnitude MS and local magnitude ML.According to three different sets of data,three new conversion relations between ML and MS have been obtained by orthogonal regression method.The result shows that：the formula MS = 1.13ML 1.08 which has been used since the 1970s has deviated from data sets severely.It is no longer suitable for new data.Considering the uncertainty of the determination of magnitudes and the discreteness of data,the paper suggests that using the formula MS = 0.03 ＋ 0.98ML as the empirical relation is more reasonable and more suitable.