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研究了甘肃地区地震活动的特征．结果表明：甘肃地区３级以上地震活动表现出明显的近３２个月的准周期性．甘肃及附近地区的６级以上大震均发生在３级地震年频次曲线的谷段附近．１９８０年以来青藏块体北缘地震活跃期内的中强地震活动的时空图象呈现多组地震自西向东有规律且稳定地迁移．各组地震迁移情况表明本活跃期地震活动已转向低潮，２００２年前后可进入平静期．青藏块体北缘西端５级以上地震的发生是甘肃地区中强以上地震活动过程开始的信号
The characteristics of seismic activity in Gansu have been studied. The results show that the earthquakes above Level 3 in Gansu Province show a quasi-periodicity of nearly 32 months. The magnitude 6 or higher earthquakes in and around Gansu occurred in the vicinity of the valley of the annual frequency curve of the magnitude 3 earthquake. Since 1980, the spatiotemporal images of moderately strong earthquakes within the active seismic active period on the northern margin of the Qinghai-Tibet Block have shown that the earthquakes of various groups migrate regularly and stably from west to east. The seismic migration of each group shows that the seismic activity in this active phase has turned to low tide and can enter the quiet period before and after 2002. The occurrence of the M ≥5 earthquakes on the northern tip of the Qinghai-Xizang block is the signal of the start of the strong earthquakes above the Gansu