利用速度型数字地震仪记录测定面波震级

Determination or surface wave magnitude by Using velocity type digital seimograph recordings

根据ＩＡＳＰＥＩ所推荐的面波震级公式，本文发展了一种利用长周期速度型数字地震仪记录测定面波震级的新方法。由于长周期数字地震仪基本上都采用速度平坦型设计，周期从３ｓ到２８０ｓ范围内仪器的放大倍数（增益）是一个常数，用本文的方法可以非常方便、准确地测定面波震级。实际计算表明，测定的面波震级与美国ＮＥＩＣ公布的结果相一致。

According to the formula of surface wave magnitude recommened by IASPEI,a new method for determining surface wave magnitude, using long period velocity type digital seismograph recordings,is developed. Due to long period digital seismographs are designed by using Velocity Smooth type, the amplification(gain)of seismographs are invariable in the range of period from 3 to 280 second. Surface magnitudes can be measured conveniently and accurately by using this method, the practice calculation indicates that the surface magnitudes measured by us are consistent with the results announced by NEIC.