新震级国家标准在大同台的应用与评估

Application and Evaluation of National Standard of New Magnitude in Datong Station

收集整理大同台在震级新国标实施以来的304个地震事件分析结果,从中筛选出宽频带体波震级m B(BB)、短周期体波震级m b和宽频带面波震级M S(BB),将其分别与美国地质调查局USGS发布的震级,及旧震级标准下的震级测定结果进行差值对比分析,对差值结果进行正态分布法检验,通过震级偏差对震级新国标在大同台的应用情况进行评估。结果表明,mB(BB)震级偏差非常小,几乎与发布震级相等;新旧m b震级基本一致,与发布震级偏差均较大,为-0.5左右;M S(BB)震级的平均偏差为0.2左右,MS(BB)震级与旧M S震级基本一致,但M S(BB)震级稳定性更好。

The analysis results of 304 seismic events of Datong seismic station since the implementation of the new national standard of magnitude were collected and sorted out,and the wide band body wave magnitude m B(BB),short period body wave magnitude mb and wide band surface wave magnitude M S(BB)were screened out from the results.The difference values were compared and analyzed with those of USGS and old magnitude standards respectively.The normal distribution method was used for the difference values test,and the application of the new national standard of magnitude in Datong station was evaluated by using the magnitude deviation.The results show that the magnitude deviation of m B(BB)is very small,almost equal to the published magnitude;the new and old mb magnitudes are basically the same,and the deviation from the published magnitude is large,about-0.5;the average deviation of M S(BB)magnitudes is about 0.2,and M S(BB)magnitudes are basically the same as the old MS magnitudes,and M S(BB)magnitudes have better stability.