目前,用微震仪记录中强地震大多数是限幅的,震级很难测定。如能在微震仪的限幅地震记录图上找到便于测量的参数,用来计算震级,这将方便台站的速报工作,具有普遍的使用价值。本文根据限幅地震记录图的显著特征——限幅时间等,拟合了限幅地震震级的计算公式,即M_L=2.37logL+0.38log(A_L×1000)/V At present, most of the moderately-strong earthquakes recorded by microseismometry are amplitude-limited, and the magnitude is hard to measure. If we can find the parameters which are easy to measure on the microseismometer’s seismogram, it will be used to calculate the magnitude, which will facilitate the quick report of the station and has universal usability. According to the significant feature of amplitude-limited seismograms, such as the clipping time, the formula for calculating the magnitude of the amplitude limiting earthquake is fitted, that is, M_L = 2.37logL + 0.38log (A_L × 1000) / V