本文是从地震监视预报实践中产生的一种方法。通过对华北地震活动高潮期规律性的认识,由b值和能量的分析中提出了最大震级Mmax—t缺震曲线的意义和方法。实际资料表明,该曲线对于华北近代中强震的发生都有较好的对应关系,在判断地震活动趋势上有一定的预测效果。 This paper is a method of earthquake monitoring and forecasting. Based on the understanding of the regularity of the upsurge of seismic activity in North China, the significance and method of the Mmax-t missing curve of the maximum magnitude are proposed from the analysis of b value and energy. The actual data shows that this curve has a good correspondence with the occurrence of the moderate strong earthquakes in the modern history of North China, and has some predictive effects in judging the seismic activity trends.