统计2009年1月1日至2011年10月30日四川青川县内8000多个M_L≥1.0地震，研究汶川地震后青川县内小震活动的日频次变化和前兆起伏加剧、突跳，与其后48小时内发生的M_L≥4.0中强震的对应关系，结果发现，对青川县中强地震发生时间、空间范围的预报分析有一定意义。

In this article the minor earthquakes M_L≥1.0 in Qing chuan during the period from January 2009 to October 2011 was statistically studied. The result indicates that before a main shock of M_L≥4.0, a series of minor events in the 48h and distances away from epicenters for the M_L≥4.0 events performance anomaly of daily frequency and premonitory fluctuation aggravation. The results show that the mutual features exist aboard in special, temporal and intensity before the main shock, and they have a practice value for analysis and diagnosis in local earthquake prediction in Qing chuan.