1966年3月河北邢台大震后,曾有过多次强余震活动。1981年11月9日又发生了5.8级强余震,截至11月30日的二十多天里共发生小震七百多次,其中4级以上的地震2次,3级以上的地震10次。这是邢台地震群中的又一个子序列。据邢台区域小台网包围震中的台站记录,用石川法测定出主震的基本参数为: After the earthquake in Xingtai, Hebei in March 1966, there were many strong aftershocks. A magnitude 5.8 aftershock also took place on November 9, 1981. As many as more than 700 minor earthquakes occurred in more than 20 days as of November 30, including 2 earthquakes of magnitude 4 or above and 10 earthquakes of magnitude 3 or above . This is another sub-sequence in the Xingtai earthquake group. According to Xingtai region station coverage of the epicenter of small Taiwan network, measured by Ishikawa method of the main parameters of the main shock: