Characteristics of zhangbei M6.2 earthquake sequence

After the Zhangbei M6.2 earthquake on January 10, 1998, comprehensive judgement was made for the earthquake sequence by b value, h value, u value and k value. The result considered that the earthquake belongs to main shock aftershock type. The Zhangbei earthquake sequence showed regular fluctuations with earthquake of magnitude 4 as peak value in attenuation process, showed relateively regular quasi-period in time and the concentration-quiet law is quite obvious before each group fluctuation.